Results and limits
This repository formalises finite results, reductions, equivalences, and obstructions related to eight Erdős problems — #68, #243, #249, #251, #257, #269, #1041, and #1049 — with #249 and #257 as the two reviewed core programmes. It does not solve any of them.
Lean source checked by the pinned Lean kernel is proof authority. The
audit log reports the headline declarations below with kernel
assumptions [propext, Classical.choice, Quot.sound]. A
theorem with hypotheses proves only the displayed implication; it does
not prove that its hypotheses occur.
Ten-minute verdict
All eight Erdős problems remain open. The development is neither a partial solution nor an empty collection of restatements. For the two reviewed programmes, its checked non-restatement centre includes:
- for #257, exact finite-period noncollapse, eventually-periodic support irrationality, a signed periodic-weight dichotomy, feedback and rank-gap theorems, and a precisely delimited squarefree-support barrier;
- for #249, exact finite-level ranks and infinite-dimensionality for dyadic sections of Euler’s totient, denominator growth for a Möbius-shadow object, and scoped barriers and case trichotomies; and
- finite evidence: a diagonal certificate band through
t=82and a historical roster of 123 distinct off-diagonal certificates (125 verified log rows), neither of which supplies the required unbounded family.
The project also audits its own conditional routes. Of 23 substantial
Lean propositions extracted from hypotheses of conditional theorems, 17
are provably equivalent to an endpoint—14 to #249 and 3 to the
1/2 membership test for #257. This is a self-diagnosis of
reformulation failure, not progress on either endpoint.
Only after those theorem-level facts comes the corpus census. The current semantic graph provides three diagnostic views across every indexed Erdős problem:
| View | #68 | #243 | #249 | #251 | #257 | #269 | #1041 | #1049 | both | shared | total |
|---|---|---|---|---|---|---|---|---|---|---|---|
| mechanically nonrecurring candidates | 0 | 3 | 88 | 0 | 168 | 0 | 0 | 5 | 0 | 19 | 283 |
| classical/prior-art formalisations | 0 | 1 | 36 | 0 | 23 | 0 | 0 | 1 | 0 | 40 | 101 |
| bare open-problem equivalences | 0 | 0 | 15 | 0 | 15 | 0 | 0 | 0 | 0 | 2 | 32 |
The nonrecurring view contains 183 unconditional object theorems, 54 scoped barriers, and 46 reductions or transports after aliases, open antecedents, bare equivalences, finite/generated instances, infrastructure, classical results, and routine corollaries are removed.
The internal adjudicated frontier shortlist contains 11 nodes; it is distinct from the 8-node public prior-art review queue. 228 nonrecurring candidates remain unassessed for prior art. The live authored open-antecedent surface has 52 clusters, of which 10 are marked endpoint-equivalent. None of these populations is a novelty census.
The large #249 denominator exclusion is a direct, kernel-checked
instantiation of the classical neighbouring-fraction/mediant method.
That method supplies the displayed bound exactly (numerical delta
0). The local addition is the checked arithmetic instance,
its transfers, and its sharp first failure.
The census is reproducible with:
python3 scripts/query_semantic.py nonrecurring
python3 scripts/query_semantic.py bare-equivalences
python3 scripts/query_semantic.py classical
python3 scripts/query_semantic.py open-antecedentsStrongest checked results by problem
One entry per problem: the strongest checked statements, their exact
status, and where to verify them. Each item carries the independent
labels used across this repository: what Lean checked, what the
statement changes, and its literature relationship.
formalised here renders known mathematics;
proved here makes no novelty claim — that judgement is a
human number theorist’s, and no query here supplies it. Reduction
targets are named with their own status in the same sentence. The
reviewed claim registry (docs/claims.json) covers the
#249/#257 core; entries marked registry: none are
kernel-checked source whose reviewed claim rows do not yet exist, and docs/problems.json is the
per-problem authority for the six expansion problems.
#68 — is ∑_{n≥2} 1/(n!−1)
irrational?
- Irrationality is equivalent, with no hypotheses, to one integer
divisibility test on exact rational prefixes failing infinitely often —
irrational_factorialGapSeries_iff_cofinal_strictFacTopRat_misses,ErdosProblems/Erdos68/FactorialZeroPlateau.lean:1090. Checked theorem; exact equivalence, transporting the difficulty without reducing it; registry: none. - The kernel-internal denominator bound is
q ≥ 67(:940); the300000exclusion is a checked implication (:876) whose evaluation is an external computation, not a kernel result. - Open: produce infinitely many non-unit carries.
#243 — does rationality force eventual Sylvester recurrence?
- A divergent natural sequence with upward steps bounded by
Bcannot stay coprime to an infinite family of fresh pairwise-coprime moduli —no_boundedRise_of_tailAvoidance,ErdosProblems/Erdos243/ReciprocalTailRigidity.lean:897. Checked theorem; reusable obstruction; registry: none. - Given normalised vanishing — supplied for the canonical orbit by
Koizumi (Integers 26 (2026), A28; cited, prose bridge) — a bounded
negative part or finite normalised negative mass forces the error to
vanish and the Sylvester recurrence to begin (
:2177,:2264;SparseResetRecovery.lean:155,:175). Checked conditional theorems; the note concedes its absorption and descent lemmas as Koizumi prior art. - Open: the unbounded mixed-sign regime.
#249 — is ∑ φ(n)/2ⁿ irrational? (reviewed
core)
- Unconditional: the dyadic sections
n ↦ φ(2ʲn+r)of Euler’s totient have an explicit rational basis, and the level-espan has dimension exactly2ᵉ + 1—finrank_canonicalTotientKernel_eq,Erdos249257/TotientMahlerDefect.lean:989; basis object at:1392. A theorem about the coefficient sequence, not about irrationality ofS; it quantifies the known qualitative fact thatφis not 2-regular (Coons 2008, arXiv:0810.3709, via ζ zero-density — no exact rank appears there). Claimdyadic_totient_certificate_interface(the basis declarations at:1265,:1380,:1392— registry: none). - Irrationality of
Shas six checked exact characterisations, from tail-difference certificates through the lcm-diagonal form to window-separated pairs —Erdos249257/LcmConeFlatness.lean:316–426,Erdos249257/PivotAntiReconstruction.lean:1775; claimscertificate_completeness,certificate_reduction. - Finite: the classical Farey/mediant window at
K = 240excludes reduced denominators through7.96 × 10³⁴— improvement over the classical bound: zero (claimdenominator_exclusion) — and diagonal certificates exist at everyt ≤ 82, with the plateau broken att = 83and a proved depth floor of125there (ErdosProblems/Skip/LadderT67.lean:71264,:71285,:71294; claimcertified_kill_instances; no certificate att = 83is claimed). - Open: the unbounded certificate supply, which is equivalent to #249 itself; a checked splice construction shows no finite inspection can settle it.
#251 — is ∑ pₙ/2ⁿ irrational?
- Unconditional:
pₙ ≤ 1250(n+1)⁴by an elementary argument, so the series is summable and equals2 +the prime-gap dyadic series with no external input (ErdosProblems/Erdos251/PrimeGapDyadicTail.lean:360,:379,:427); and for any sequence obeying the checked integer-digit dyadic tail recurrence, irrationality is exactly equivalent to cofinal non-integral tail shifts (irrational_initial_iff_cofinalNonintegralTailShifts,:1572) — the identification of the concrete prime tail with that recurrence is paper-level. Checked theorems; registry: none. - A checked countermodel closes the periodicity route: an explicit
unbounded, non-eventually-periodic digit sequence with rational dyadic
sum (
carryCoeff_natCast_not_eventually_periodic,:1163). - Open: cofinally many adjacent index pairs with small tail shifts and differing gaps; each smallness condition constrains a complete infinite tail.
#257 — is ∑_{n∈A} 1/(2ⁿ−1) irrational for every
infinite A? (reviewed core)
- Native unconditional: for every finite nonempty support
Fof positive exponents and every baseb ≥ 2, the reduced denominator of∑_{n∈F} 1/(bⁿ−1)is coprime toband has multiplicative order exactlylcm F—finite_period_noncollapse,Erdos249257/CertificateKernel.lean:5091, with no witness-supply hypothesis. Checked theorem; registry: none. - Formalised known results: the full-support series is irrational in
every base
b ≥ 2(Erdős 1948; claimeb_full_support), as are pairwise-coprime supports with summable reciprocals (Erdős 1968) and eventually periodic supports. - The base-2 Mersenne achievement set — all subsums of
∑ 1/(2ⁿ−1)— is compact, perfect, totally disconnected, nowhere dense, and of Lebesgue measure one (strict-tail Cantor structure after Kovač–Tao, Remark 4.1; the measure clause is proved here; positive measure was asserted informally by Kovač on the erdosproblems.com #257 discussion page in August 2025, and no published source computes the exact value) —Erdos249257/GreedyAchievementSet.lean:996,:1633–1658; claimgreedy_achievement_geometry. Membership of1/2is equivalent to infinitely many greedy skips (:2527) and to the absence of a fatal half-gap (Erdos249257/HalfCutLocator.lean:654); the dyadic membership question was posed publicly by Kovač in the same discussion, and a positive answer would refute universal #257. - Methodological: a formalised squarefree-support no-go theorem is
shown to be an artefact of normalisation — adjoining
1to the support shifts the value by a rational and flips the divisor-incidence parity, and the finite-change principle is itself checked (ErdosProblems/Erdos257/SquarefreeSupportIncidence.lean:94,:111,:140;Erdos249257/CertificateKernel.lean:9467,:9476). The squarefree value itself is settled at power-of-two bases in the literature (Duverney–Tachiya 2019; cited, not formalised). Registry: none. - Open: universal #257, and the
1/2and1/21memberships.
#269 — are reciprocal sums of running lcms irrational?
- For every pair of distinct primes, both the de-duplicated and the repeated running-lcm reciprocal sums are transcendental — a paper argument in the problem note; the transcendence engine is Loxton–van der Poorten 1977, quoted in the modern Bugeaud–Laurent form (Theorem 1.1); deliberately not a Lean theorem, and the note says so. Independently found and not first: the same reduction and conclusion were posted by Steve Fan on the erdosproblems.com #269 discussion page on 26 June 2026, before the note was finalised, with follow-ups there extending it to arbitrary coprime pairs; the note acknowledges this.
- Lean-checked: the exact running-lcm product
L(x) = p^⌊log_p x⌋ q^⌊log_q x⌋ r^⌊log_r x⌋(ErdosProblems/Erdos269/ThreePrimeRunningLcm.lean:123; formalisation of a classical identity), the four-letter block alphabet{2, 6, 10, 30}(:699), and a rank-two kernel obstruction (:479,:721). - Open: any three-prime case; the rationality-to-carry bridge and the cofinal window escape.
#1041 — short connections inside polynomial lemniscates?
- Checked: quantitative root retention under constant perturbation
(
constant_perturbation_roots_in_unitDisk,ErdosProblems/Erdos1041/NewtonFlowRaySeparation.lean:287) and arbitrarily small translations separating all pairwise ray arguments (:197). The ray-separation exclusion is checked in consumer form only: the exponential-decay connection equation is its hypothesis, not a theorem (:315). Registry: none. - The note’s main independent contribution is prose, not Lean: a specific invalid three-ended local block at an interior Morse saddle in a recent manuscript’s load-bearing Proposition 12 — identified as a proof gap, not a counterexample.
- Open: repair or refute that decomposition; the planar topology and length bookkeeping.
#1049 — Lambert series at rational bases, beginning with
3/2?
- Checked exclusions at
3/2, each of one named mechanism only: the coordinatewise clearing scheme is impossible for all parameters (threeHalves_no_coordinatewiseCorridor,ErdosProblems/Erdos1049/RationalBaseLambert.lean:155), scalar content is neutral for the local-to-Archimedean balance, and unit endpoints exclude both2and3from a common divisor (ErdosProblems/Erdos1049/ZudilinConeArithmetic.lean:293). Registry: none. - The elementary height inequality used by Bundschuh–Väänänen’s
external irrationality criterion at
7/2is checked (RationalBaseLambert.lean:83); the analytic theorem itself remains external. Formalisation of known inputs. - The Van Assche moving diagonal fails the Amdeberhan–Zeilberger
scalar recurrence already at
n=0: its exact residual is-p(p-1)^2(p+1)(p^5+2p^4+2p^3+2p^2+2), strictly negative for every realp>1(QAperyDiagonalNonEquivalence.lean:67,94). This finite obstruction proves only non-transfer of that recurrence; it supplies no general recurrence, endpoint, lattice, valuation, denominator, or irrationality theorem. Registry: none. - Open: irrationality at
3/2; the primitive noncollapsed construction; analytic remainder control. The note proves no irrationality result and says so.
The semantic corpus marks exactly eight statements
candidate_new_statement — the only machine novelty marks in
this release, against 5,460 of 6,036 statement nodes still
not_assessed. They concentrate in the #249/#257 core (the
totient Möbius-numerator normal form, a rank-one overshoot barrier, and
the 1/2 tail-escape and middle-producer family). Reproduce
the list from docs/semantic_corpus.json
(statement_nodes[].prior_art_state); candidate status is a
search outcome recorded for triage, not a novelty claim.
What is proved
Settled support families for Problem 257
The universal problem is open, but several infinite supports are
settled. The formal source proves irrationality in every integer base
b≥2 for the full support, factorials, powers of two,
multiples of a fixed positive integer, residue classes, the odd numbers,
eventually periodic supports, and pairwise coprime supports with
summable reciprocals. The relevant declarations include:
irrational_erdosSum_full_support;erdos257_family_factorial_instanceanderdos257_family_two_pow_instance;irrational_erdosSupportSeries_multiples,irrational_erdosSupportSeries_residueClass, andirrational_erdosSupportSeries_odd;irrational_erdosSupportSeries_eventuallyPeriodic; andirrational_erdosSupportSeries_pairwise_coprime.
These declarations are in
Erdos249257/CertificateKernel.lean. The prime and
prime-power supports are literature results cited by the repository, not
formalised here.
The squarefree support remains open. Its divisor incidence is proved
to be 2^ω(n)-1, hence odd at every n≥2. The
certificate engines in this development begin by selecting an
even-incidence block, so they cannot act on that support at any block
position. The checked declarations card_squarefreeDivisors,
squarefreeIncidence_eq, and
odd_squarefreeIncidence are in
ErdosProblems/Erdos257/SquarefreeSupportIncidence.lean.
This is a limitation of the named engines, not evidence that the
squarefree-support value is rational or irrational.
The reduction chain for the one-half test case of Problem 257
The Mersenne achievement set consists of subsums of
1/(2^n-1). If 1/2 belongs to it, its support
gives an infinite set with a rational subseries, which would refute the
universal statement in Problem 257. The repository does not prove this
membership.
The checked chain includes:
half_mem_mersenneAchievementSet_iff_greedySkippedSupport_infiniteinErdos249257/GreedyAchievementSet.lean: membership of1/2is equivalent to infinitely many skips in its greedy expansion.half_mem_mersenneAchievementSet_iff_unboundedTerminalFalseinErdos249257/HalfCylinderHalfMembershipClassification.lean: the same membership is equivalent to terminal false bits beyond every bound.half_mem_iff_unboundedLargestSkipLateinErdosProblems/Skip/D2.lean: membership is equivalent to late largest skips beyond every bound.exists_largestSkipLateAt_of_remainder_le_two_powinErdosProblems/Bit/R2.lean: a row with remainder at most2^Nproduces a late largest skip in the explicit interval[N+1,2N+1].half_mem_of_remainderReachesHalfPointCofinallyinErdosProblems/Bit/R2.lean: remainders at most2^scofinally are sufficient for membership.
The final two bullets are one-way sufficient criteria. They are not equivalences and are not known to hold cofinally.
The proposed universal hlow side condition is false:
not_hlow_seven_five in
ErdosProblems/Decl/D4.lean and
not_hlow_of_hhigh in
ErdosProblems/Hlow/H1.lean give the counterexample
(s,d) = (7,5). Its failure is useful rather than
obstructive: seamRemainder_lt_two_pow_of_not_hlow and
seven_is_a_hit_from_failure in
ErdosProblems/Hlow/H2.lean convert that failure into a hit
certificate.
Exact ranks for dyadic sections of Euler’s totient
For j ≥ 0 and 0 ≤ r < 2^j, let
φ_(j,r)(n) = φ(2^j n + r). The family consisting of
φ_(0,0), φ_(1,0), and all φ_(j,r)
with odd r is a rational basis for the span of all dyadic
sections. At level e, the span has dimension exactly
2^e + 1.
Lean names and sources:
linearIndependent_oddCoreTotientKernelFamily,span_range_fullTotientKernel_eq_span_range_oddCore, andtotientDyadicSectionBasisinErdos249257/TotientMahlerDefect.lean;finrank_canonicalTotientKernel_eqin the same file.
These are theorems about the coefficient sequence φ.
They do not prove that ∑ φ(n)/2^n is irrational.
A finite diagonal certificate band for Problem 249
Let periodLcm t = lcm(1,…,t). The predicate
certifiedKill h N L is a finite modular-arithmetic
certificate showing that a specific binary totient-tail difference at
shift h and position N is not an integer.
exists_diagonalKill_le_82 proves
for every t ≤ 82, there is an L such that
certifiedKill (periodLcm t) (periodLcm t) L.
Lean name and source:
exists_diagonalKill_le_82—ErdosProblems/Skip/LadderT67.lean
The exact least depths at the new boundary scales are:
Scale t |
Least depth L |
Lean name | File |
|---|---|---|---|
| 67 | 100 | t67_minimal_depth |
ErdosProblems/Lift/Recon67.lean |
| 71 | 105 | t71_minimal_depth |
ErdosProblems/Lift/CertT67.lean |
| 73 | 113 | t73_minimal_depth |
ErdosProblems/Skip/LadderT67.lean |
| 79 | 120 | t79_minimal_depth |
ErdosProblems/Skip/LadderT67.lean |
| 81 | 120 | t81_minimal_depth |
ErdosProblems/Skip/LadderT67.lean |
The same file proves
periodLcm 79 = 32433859254793982911622772305630400,
a 35-digit modulus, as periodLcm_79_value.
The source-backed checked_diagonal_depth_roster.json
covers all 33 distinct periodLcm scales whose plateaux fill
the positive band t≤82. Every recorded working depth lies
0…4 above the arithmetic admissibility floor (median
1, mean 40/33). Only the five boundary scales
t=67,71,73,79,81 have separate theorems proving their
recorded depths least; for the other 28 scales, the excess is only an
upper bound on the least-depth excess. Reproduce the roster with:
python3 scripts/build_checked_diagonal_depth_roster.py --checkThis is a bounded result. The reduction for Problem 249 requires
certificates at arbitrarily large scales. The theorem says nothing at
t = 83.
Finite off-diagonal certificates
The historical audit selects 125 verified log rows at positions not
constrained to equal periodLcm t. Two pairs of rows repeat
the same (h,N,L) triple, so the roster contains 123
distinct certificates matched to 123 public Lean theorems across 122
files. The largest position in that audited set is:
freeKill_64OneHundredFifteenDI :
certifiedKill 1 135960691671824579163806583999 101
Source:
ErdosProblems/FreePosition/FreeKill64OneHundredFifteenDI.lean.
The generated off_diagonal_certificate_roster.json
retains all selected source rows and their hashes, identifies both
duplicate groups, and binds each distinct triple to its exact theorem,
line, and source hash. Reproduce it with:
python3 scripts/build_off_diagonal_certificate_roster.py --checkThe source log also contains 54 later verified certificate triples above the historical position cutoff. The roster exposes that excluded census without silently changing the historical result.
The relevant sufficient theorem for Problem 249 is
irrational_totient_series_of_multiple_window_kill_supply in
Erdos249257/CertificateKernel.lean. Its hypothesis
requires, for every positive base shift and every lower bound on the
position, a later certificate at some positive multiple of that shift. A
finite list of 123 instances does not establish that quantified
supply.
Direct Farey comparison
The denominator exclusion is exactly the standard Farey/mediant bound for the two committed finite windows. The arithmetic below was recomputed from
V_K = (∑_{r=1}^K φ(r+1) 2^(K-r)) mod 2^K
and from the explicit neighbouring fractions in
Erdos249257/GapFareyBound.lean.
K |
Interval width | Delta |
|---|---|---|
| 120 | 123/2^120 |
0 |
| 240 | 243/2^240 |
0 |
The exact denominators of each window are:
K = 120
Farey neighbour denominators b, d 41326538792622579
207345787569745331
b+d-1 248672326362367909
formal exclusion bound 248672326362367909
first failing denominator 248672326362367910
K = 240
Farey neighbour denominators b, d 66013429300517684370587633721421187
13626217346183690952768141154409867
b+d-1 79639646646701375323355774875831053
formal exclusion bound 79639646646701375323355774875831053
first failing denominator 79639646646701375323355774875831054
For each window, the recomputation gives determinant 1
for the two neighbours, verifies both interval brackets, verifies the
displayed bound, and verifies failure at the next denominator. The
corresponding proved declarations are farey_gap,
gap_check_window_1_120_le_248672326362367909,
gap_check_window_1_120_first_failure,
gap_check_window_1_240_le_79639646646701375323355774875831053,
and gap_check_window_1_240_first_failure.
The division of credit is exact: Farey supplies the bound directly; formalisation supplies a checked arithmetic instance and proves it is sharp for that window. Neither finite window proves that the exclusion bounds are unbounded, so neither proves Erdős #249.
The magnitude is also a tunable window output, not an invariant
measure of progress.
scripts/check_farey_denominator_scaling.py independently
reproduces the two formalised constants and cross-checks the producer by
brute force on six small windows. On this run, choosing
K=16000 produced a 2,406-digit bound in 0.08
seconds for the scaling row (0.18 seconds for the complete
script). Every fixed K still gives only a finite exclusion,
and increasing K does not supply the unbounded theorem
required by #249.
Scoped no-go theorems
These theorems rule out particular proof mechanisms. They do not rule out other arguments.
no_lift_from_lower_totient_data,ErdosProblems/Lift/AngleA5.lean— no universal lift of the displayed form can follow only from the stated lower totient data, pointwise bound, and a lower certificate.no_window_local_lift,ErdosProblems/Lift/InduceLaw.lean— for prime multipliersp ≥ 3, agreement on the lower diagonal window does not force any certificate in the lifted window.exists_certifiedKill_antitone,ErdosProblems/Lift/AngleA4.lean— a certificate at a larger position gives one at a smaller position; the implication runs opposite to a forward lift.consecutiveFail_iff,ErdosProblems/Half/FreeWalk2.lean— under its explicit depth inequality, a run ofKfailures at depthLis equivalent to failure at depthL+Kat the base position.no_absolute_bound_on_consecutive_failures,ErdosProblems/Half/FreeWalk1.lean— the abstract admissible-run model permits arbitrarily long failure runs under its stated budget.exists_persistent_surplus_model,ErdosProblems/Rem/C1.lean— the listed row recurrence and ceiling inequalities admit a sequence that stays above the target forever.rowLaw_blind_at_16,ErdosProblems/Rem/C1.lean— at one concrete row, every listed row-level trigger is silent although the next row has a late skip.IntervalCeiling.four_pow_le,ErdosProblems/Three/T1.lean— every ceiling satisfying the stated branch-blind rank-recursion obligations must grow on the4^sscale.two_pow_mul_y,ErdosProblems/Three/T2.lean— the normalised state used in the doubling route is dyadic at every finite row.exists_persistent_odd_surplus_model,ErdosProblems/Three/T3.lean— adding parity to the listed row-level constraints still admits a persistent surplus model.PairCeiling.terminal_ge_of_splits,ErdosProblems/Decl/D1.lean— in the stated two-sided abstraction, a failed branch prediction forces the terminal upper bound above the target scale.
Other standalone exact obstructions
These five registry claims are not restatements of either endpoint. Each has a separate limitation, and none settles an Erdős problem.
totient_carry_kernel_anti_compression— ifSwere rational, one rationality-supplied tempered integral carry would have canonical carry-section span dimension at least2^e-1for everye. Boundary: no finite-rank upper bound for such carries is known, so this does not contradict rationality.primitive_coordinate_index_obstruction— clearing(φ*μ)(n)/nthrough levelNforces a two-tier primorial divisor; no fixed positive index clears every level. Boundary: finite Euler-coordinate obstruction, not an irrationality criterion.lcm_factor_ideal_anchor_pulse_no_go— for everyt≥3, a synthetic survivor satisfies the factor-ideal and whole-ray-anchor constraints and survives every finite integer shift polynomial. Boundary: its letters need not be actual totient differences; nonlinear fresh-divisor arguments remain possible.reciprocal_mass_bound— a rational support value with odd denominator partvforces reciprocal mass at least1/ord_v(2), or divergence; a dyadic-rational infinite support forces divergence or mass greater than one. Boundary: does not exclude every rational value.unbounded_carry_states— every infinite support with rational series value has an unbounded positive carry state. Boundary: rules out finite-state interpretations, not rationality itself.
Retrieve their declarations and current source coordinates with
python3 scripts/query_corpus.py --claim <registry-id>.
Demand ledger
A demand is an unproved hypothesis extracted from a conditional
theorem and stored as a named Lean proposition.
ErdosProblems/DemandLedger/Basic.lean contains 101 named
closed propositions; 23 are labelled substantive and the rest are side
conditions. The current prose frontier contains 52 entries.
The extraction snapshot in the audit log records 144 proved implication edges among the 23 substantive demands, producing seven equivalence classes. Seventeen substantive demands collapse to restatements of an open target rather than smaller subproblems. For example:
G103_iff_erdos249inErdosProblems/DemandLedger/edges/Discharge3_G103.leanproves that the general lcm-window supplyG103is equivalent to Problem 249 itself.G103_iff_G097in the same file identifies two supply formulations.e_G083_G084inedges/ClusterE.leanrecords one implication in the Problem 257 chain.
The ledger classifies obligations. It does not discharge an obligation merely by naming it or proving it equivalent to the target.
What is measured, not proved
Only measurements with an explicit tested range and explicit exception set are listed here. Counts without preserved sample identities are not promoted to release results.
| Measurement | Exact range | Exact failures or mismatches | Status |
|---|---|---|---|
Recon257.seamExcess s = 2 |
s = 5,…,102 (two overlapping scans, 5…64
and 58…102) |
No occurrence. | MEASURED. This makes the audited uses at s=D+1,
D≥60, unobserved. |
Three-row hcof on the seven audited survivor
values |
D = {101,122,164,314,545,629,1112} |
Fails at all seven values. | MEASURED; every audited case satisfying hcof already
died by depth 3. |
| Residual invariant | s = 6,…,3000, d = 2,…,s-1 |
Exactly (s,d)=(13,7); residual 524419,
bound 524288. |
The exception is also PROVED by
Three/T1.not_residualInvariant. |
hlow and hhigh at late pairs |
all late pairs with s = 5,…,600 |
hlow fails exactly at (7,5);
hhigh fails exactly at (5,4). |
The hlow exception is PROVED in Decl/D4
and Hlow/H1. |
| Remainder-hit/greedy-support correspondence | s = 5,…,900 |
Zero mismatches. | MEASURED. It does not prove infinitely many hits. |
UnboundedLargestSkipLate row event |
s = 5,…,1500 |
Fails exactly at s = 5,11,12,13. |
MEASURED. A finite interval does not prove eventual or unbounded behaviour. |
| Residual invariant on adjacent control rows | every rank of rows s=12 and s=14 |
No failures. | MEASURED anti-vacuity check for the isolated (13,7)
counterexample. |
| Diophantine height at one scale | d=1000 |
Denominator bit length 253815; comparison value
d²/4=250000. |
MEASURED single-scale size check, not an asymptotic theorem. |
| Relative-margin scan | d = 2,…,2000 |
Record low 1.13×10^-4 at d=1136; no
danger-zone instance. |
MEASURED. It does not establish a positive lower bound. |
For the residual invariant, the maximum ratio away from the exception
was 0.9999807 at (606,602).
The rows above are carried from a dated audit log whose raw run logs
and executable scan owners are not preserved in this release. Their
stated finite domains and exception sets are therefore historical
measurement records, not independently reproducible artifacts. A
reported late-bit scan of about 14,000 ranks over
s=14,…,400 is omitted from the table because neither its
exact sample count nor its sample identities were preserved.
The audit also records a selection-biased certificate sample: at
depth excess c=2, 15 of 154 samples failed; at
c=3, 601 of 5987 failed. The sample identities are not
preserved in the log, so these counts are not independently
reconstructible from the release and are not evidence for an
equidistribution law.
The remaining two measurements are source-backed and reproducible from this release.
Exact endpoint-certificate probe
Exact range: all 960 pairs 1≤N≤120,
1≤h≤8, searching 1≤L≤400; additional
h=1 probes at N=200,500,1000,2000,5000; exact
LCM-diagonal pairs (N,h)=(lcm(1,…,t),lcm(1,…,t)) for
1≤t≤16.
Exact failures or mismatches: no failures. Relative to the least
arithmetically admissible depth
L₀=min{L≥1:2ᴸ>2(N+h+L+2)}, the rectangle’s first
certificates have excess 0…11 (median 1, mean
727/480); the 16 indexed diagonal rows have excess
0…4 (median 1, mean 5/4), and the
11 distinct diagonal scales have mean 14/11.
Status: MEASURED by exact integer arithmetic. Raw depth must grow
with scale because the certificate interval is empty below
L₀; the finite excess distributions prove no asymptotic
law, equidistribution, bounded-excess theorem, or cofinal supply.
Reproduce with:
python3 scripts/probe_certificate_supply.py --checkSource-backed checked diagonal depths
Exact range: all 33 distinct periodLcm scales covering
positive t≤82.
Exact failures or mismatches: every checked working depth has excess
0…4 over L₀ (median 1, mean
40/33). Five rows have proved least depths, with exact
excess 0…3; the other 28 values are upper bounds on
least-depth excess.
Status: FINITE SOURCE EXTRACTION from explicit Lean theorem signatures. It establishes no bounded-excess law at untested scales and no cofinal supply. Reproduce with:
python3 scripts/build_checked_diagonal_depth_roster.py --checkWhat was retracted
The detailed file-by-file record is in TRUTH_AUDIT.md. The main
corrections are:
Lift/AngleB2.leanno longer says that the survivor set is empty. Its theorem is conditional on a falsehcofinstance at each surviving class and on an unobservedseamExcess = 2hypothesis.Lift/AngleB3.leanno longer presentsratchetOrbit_above_universal_barrieras a live universal barrier. Its intended hypothesis fails at the initial row, and the proved nonrecurrence result covers only offsetsb ≥ Q+2, not offsets1,…,9. The file now uses an actual Lean bridge toRecon257.Skip/D1.leanandSkip/Wire1-3.leanno longer claim to exclude residue classes. Their existential threshold exceeds every case admitted by their own hypotheses, and the same unobserved seam-excess premise remains.Rem/C6.leanno longer says the residual invariant is empirically true ons = 6,…,3000. It is false at(13,7).Rem/C3.leannow distinguishes the branch it proved from the branch it only measured at the time, and points toThree/T2.lean, where the latter branch was subsequently proved.Bit/R2.leanlabelsbadRun_pins_remainderas a conditional statement with no observed instance: it needs at least 12 consecutive bad rows, while the measured maximum was 3.Three/T4.leanandBit/Corr1.leanno longer callhlowopen. It is false at(7,5), and that failure supplies a hit certificate.
No theorem was weakened or removed to make these corrections. The claims were narrowed to the theorem types and the recorded counterexamples.
What is open
Exact questions for a human expert
The command
python3 scripts/query_semantic.py expert-questionsreturns a bounded index of the validated handoffs. Open one complete packet with, for example,
python3 scripts/query_semantic.py expert-questions XQ249-pivot-decorrelationEach requested input is OPEN; the consumer named under
each question is a checked theorem. The classification matters: the
first question is the endpoint in exact normal form, the next two are
sufficient analytic producers for #249, and the last two would produce a
counterexample to universal #257 rather than prove its positive
statement.
No checked strictly weaker handoff currently implies the universal positive statement of #257 for every infinite support. Named support families, half-value analysis, reciprocal-mass bounds, and sublogarithmic zero-window constraints are partial; treating any one as a universal proof route would overstate what its checked consumer establishes.
The packet does not make an expert start cold. Every ask also carries a low-confidence current hypothesis, enumerated alternatives, current evidence, and the observation or theorem that would distinguish them; both are recorded with each question below.
XQ249-lcm-diagonal-supply — diagonal supply
Exact OPEN input: for every t₀, find
t ≥ t₀ and L with a diagonal certificate at
(lcm(1,…,t), lcm(1,…,t)).
Payoff and boundary: equivalent to #249. A proof closes #249; until then this is a restatement, not intermediate progress.
Current working guess: certificates occur beyond every scale, equivalently #249 is true.
Evidence that would change the guess: a rational representation or an
eventual-failure theorem decides the opposite branch. The exact
rectangle has first-depth excess 0…11; across all 33
distinct checked diagonal scales covering t≤82,
working-depth excess is 0…4 (median 1, mean
40/33). Only five diagonal depths are proved least, and
finite low upper bounds neither prove bounded excess nor decide the
cofinal quantifier.
PROVED consumer:
irrational_totient_series_iff_lcm_diagonal_certificate_supply
XQ249-pivot-decorrelation — pivot decorrelation
Exact OPEN input: cofinally supply the exact four pivot
budgets: centred real correlation ≤14X/25, supplier mean
and bad-supplier norms ≤X/100 each, and non-supplier norm
≤8X/25, with overlap h≤L-s and room
16(2X+h+L+2)≤2^L.
Payoff and boundary: sufficient for #249. The missing input is a prime-distribution or residual-decorrelation estimate, not another certificate reformulation.
Current working guess: for every shift, fixed s,η permit
cofinally many blocks satisfying overlap, room, and all four budgets;
the centred real term is likely the hard budget.
Evidence that would change the guess: exact failure requires one
shift for which every s,η eventually loses at least one
clause. Infinitely many bad blocks do not suffice. An exact four-budget
producer proves #249.
PROVED consumer:
irrational_totient_series_of_pivotResidualDecorrelation
XQ249-adjacent-phase-separation — adjacent phases
Exact OPEN input: for every h>0 and
X₀, find X≥max(X₀,1), a depth L,
and adjacent N,N+1∈[X,2X) such that
16(2X+h+L+2)≤2^L and their first-harmonic phases have
squared chordal separation at least 19/25.
Payoff and boundary: sufficient for #249. Finite scans or average separation do not meet the cofinal quantifiers.
Current working guess: qualifying adjacent separation occurs cofinally for every shift.
Evidence that would change the guess: one shift and a cutoff beyond
which no admissible block, depth and adjacent pair reaches
19/25 kill this route; infinitely many bad blocks alone do
not. A cofinal adjacent-discrepancy theorem at that threshold proves
#249.
PROVED consumer:
irrational_totient_series_of_adjacentPhaseSeparation
XQ257-second-channel-separation — second channel
Exact OPEN input: prove
HalfSecondChannelSeparatedRat n for every n≥7,
i.e. that the exact rational second-channel phase stays at least
1/6+(37/56)2^{-n} from 1/3; Lean checks
1,…,6, and an independent exact probe finds no failure
through n=1000.
Payoff and boundary: proves 1/2 attainable. The
finite-support exclusion then forces the witness to be infinite, giving
a rational counterexample to universal #257. The finite probe does not
move the quantifier; failure of this route would not prove universal
#257.
Current working guess: the separation continues for all
n≥7; confidence remains low despite an empty exact failure
set on 1≤n≤1000.
Evidence that would change the guess: the least measured margin on
the open range is 1033253069/8193024 at n=7,
but n=1001 onward is unmeasured. One failed level closes
only this socket; a global reachability invariant or uniform sign
estimate proves membership and, with finite-support exclusion, a
counterexample.
PROVED consumers:
half_mem_mersenneAchievementSet_of_secondChannelSeparationRat_from_seven
positiveMersenneSupportValue_coe_finset_ne_half
positiveMersenneSupportValue_eq_erdosSupportSeries
The second-channel measurement is source-bound and reproducible:
python3 scripts/probe_second_channel_separation.py --checkIt re-evaluates the rational greedy recurrence and the complete
failure set for 1≤n≤1000 from the definitions in
Erdos249257/GreedyAchievementSet.lean. The generated
artifact is docs/measurements/second_channel_separation_probe.json.
Its status is MEASURED, not PROVED; in
particular, the empty finite failure set does not establish the
all-n hypothesis consumed by the Lean theorem.
XQ257-middle-producer-tail-escape — middle
producer
Exact OPEN input: at every actual middle transition from
rank 13, write C for the checked producer
carry and Θ for its nonnegative coefficient tail. Prove
C=-3 or (1≤C and Θ<C).
Payoff and boundary: also proves 1/2 attainable; at the
putative last-false row the checked -3 theorem removes the
first disjunct, and the finite-support exclusion then forces an infinite
witness. The socket must exclude every actual C≤0,
C≠-3, and control Θ<C for every positive
cell.
Current working guess: every actual middle row lies in the
C=-3 branch or has 1≤C and
Θ<C.
Evidence that would change the guess: one actual nonpositive cell
other than -3, or one positive cell with Θ≥C,
refutes this socket. A proof of the displayed disjunction at every
actual row proves membership; the final -2 sieve alone does
not.
PROVED consumers:
half_mem_mersenneAchievementSet_of_middleProducerTailEscapeExceptNegThree
positiveMersenneSupportValue_coe_finset_ne_half
positiveMersenneSupportValue_eq_erdosSupportSeries
Exact systems-review handoff
The repository cannot certify its own human legibility. It therefore
exposes a second OPEN question: can an independent reader,
starting from a fresh clone, recover the calibrated verdict in at most
ten minutes? The request is exact, including the response schema, its
consumer, payoff, and boundary:
The low-confidence working guess is that a reader will recover both open boundaries and the zero Farey delta, but may still underweight the concrete non-restatement results. The protocol distinguishes that failure from the opposite error—mistaking finite or conditional results for a near-solution.
python3 scripts/query_expert_handoffs.py --domain systems
python3 scripts/query_expert_handoffs.py --question XQ249-pivot-decorrelation
python3 scripts/query_expert_handoffs.py --template XQSYS-ten-minute-hostile-reader
python3 scripts/query_expert_handoffs.py --response RESPONSE.json
python3 scripts/query_expert_handoffs.py --review-template XQSYS-ten-minute-hostile-reader
python3 scripts/query_expert_handoffs.py --review RESPONSE.json REVIEW.jsonA structurally accepted response from an identified independent reader returns an explicit rubric for its result summaries, evidence paths and verdict. A second identified evaluator binds a final review to the response digest. The validator cannot authenticate either person or the elapsed time, and does not pretend to judge free prose by itself. Neither receipt validates the mathematics or establishes priority or novelty. The same query without a domain filter returns this systems question beside the five theorem-connected mathematical questions; respondent-facing output omits the evaluator’s scalar answer key.
Erdős Problem 249
The irrationality of
∑_{n≥1} φ(n)/2^n
is open. The finite band through t=82 and the 123
distinct certificates in the bounded historical off-diagonal roster do
not provide the quantified, unbounded certificate supply required by the
reduction.
Erdős Problem 257
The statement that
∑_{n∈A} 1/(2^n-1)
is irrational for every infinite A is open. In
particular, membership of 1/2 in the Mersenne achievement
set is not proved.
At level d, the rational compared with the remaining
tail changes with d. A naive common-denominator
construction gives an upper height bound of the form
2^O(d^2), but the repository proves neither a matching
lower bound nor a Theta(d^2) law for the reduced
denominator along the actual greedy support. The displayed separation
boundary has an explicit correction proportional to 2^{-d}.
No registered theorem controls the required sign uniformly at this
moving boundary, and there is no fixed rational approximation target to
which a fixed-number theorem applies directly.
Irrationality alone is insufficient because the open branch asks for the sign of a nonzero tail difference, not merely for non-equality.
How to verify
Install the pinned Lean toolchain and Mathlib cache, then run:
lake exe cache get
lake build
python3 scripts/build_declaration_atlas.py --check
python3 scripts/build_semantic_corpus.py --check
python3 scripts/check_semantic_corpus.py
python3 scripts/build_corpus_descriptor.py --check
python3 scripts/test_declaration_head_contract.py
python3 scripts/test_projection_checkout_independence.py
python3 scripts/check_cold_clone_comprehension.py
python3 scripts/check_release.pyFocused checks for the headline Lean files are:
# These dependency chains are not imported by the root build. Install their
# `.olean` files before running the direct checks downstream.
lake build ErdosProblems.Lift.Recon67 ErdosProblems.Lift.CertT67
lake build ErdosProblems.Three.T1 ErdosProblems.Decl.D4
lake env lean ErdosProblems/Skip/LadderT67.lean
lake env lean ErdosProblems/FreePosition/FreeKill64OneHundredFifteenDI.lean
lake env lean ErdosProblems/Three/T1.lean
lake env lean ErdosProblems/Decl/D4.lean
lake env lean ErdosProblems/Hlow/H2.leanThe lake build step emits build progress and
kernel-dependency reports. An exit status of zero and empty output is
expected from each subsequent lake env lean check.
Isolated-tree reproduction record
Measured on 2026-07-26 on an Apple M4 host (arm64, 10
logical CPUs, 24 GiB memory). The source was copied without
version-control metadata or a prior .lake directory:
# Run from anywhere inside a clone of this repository.
repo_root=$(git rev-parse --show-toplevel)
repro_dir=$(mktemp -d)
rsync -a --exclude '.git/' --exclude '.lake/' "$repo_root"/ "$repro_dir"/
cd "$repro_dir"
lake exe cache get
lake buildThe cache fetch exited zero in 109.73 seconds. The root
build completed all 8,914 jobs and exited zero:
real 4194.17
user 15939.05
sys 4778.79
The build printed ordinary dependency reports and linter warnings. It did not install every object needed by the focused expansion files. The following dependency builds supplied the two missing chains:
| Command | Exit | Wall time |
|---|---|---|
lake build ErdosProblems.Lift.Recon67 ErdosProblems.Lift.CertT67 |
0 | 195.37 s |
lake build ErdosProblems.Three.T1 ErdosProblems.Decl.D4 |
0 | 126.47 s |
With those objects installed, every direct focused check exited zero
with empty Lean output. The directories and files below are relative to
ErdosProblems/.
| Directory | File | Wall time |
|---|---|---|
Lift |
Recon67.lean |
69.24 s |
Lift |
CertT67.lean |
98.81 s |
Skip |
LadderT67.lean |
682.69 s |
FreePosition |
FreeKill64OneHundredFifteenDI.lean |
53.05 s |
Three |
T1.lean |
8.83 s |
Decl |
D4.lean |
6.76 s |
Hlow |
H2.lean |
5.27 s |
Two commands did not reproduce in the original advertised order.
Immediately after the root build, checking LadderT67.lean
failed in 1.74 seconds because the Recon67
object was absent. Directly checking Recon67.lean and
CertT67.lean did not install their objects, so a second
LadderT67.lean attempt failed in 2.02 seconds
for the same reason. The first direct T1.lean attempt
likewise failed in 1.93 seconds because the
Rem.C6 object was absent. The focused recipe above now uses
lake build for both dependency chains before the direct
checks.
The repository also contains a source-bound receipt runner:
python3 scripts/run_source_bound_reproduction.py plan
python3 scripts/test_source_bound_reproduction.pyIt hashes the declared source tree, executes the complete command
plan in an isolated copy, records command vectors, UTC bounds, exit
codes, wall/user/system times, output digests and bounded tails, and
validates the resulting receipt against the source identity. The
release-check row is explicitly marked as requiring version-control
metadata; a default run refuses that capability unless it is separately
authorised. No complete receipt is shipped at
docs/measurements/source_bound_reproduction_receipt.json
yet. Accordingly, the timings above remain a dated manual record rather
than a machine-revalidated receipt for the present source tree.