Plectis Atlas
Euclidean signed and reordered prefix bounds
Family 097: The Euclidean Steinitz–Bergström bound
Candidate pairing
Corollary (Finite-dimensional \ell_p bounds)
Let 1\le p\le\infty, with 1/\infty=0, and let d,N\ge1 be integers. Every sequence v_1,\ldots,v_N\in\R^d with \lVert v_i\rVert_p\le1 admits signs \varepsilon_i\in\{-1,1\} such that
If additionally \sum_{i=1}^N v_i=0, there is a permutation \pi\in\mathfrak S_N such that
Here C is the same absolute constant as in Theorems thm:signing and thm:steinitz, independent of p,d,N. For 1\le p\le2, both bounds have sharp dimension order d^{1/p}: for every d there is a unit-ball sequence for which every signing has a prefix of norm at least d^{1/p}, and a finite indexed zero-sum unit-ball family for which every permutation has a prefix of norm at least \tfrac13d^{1/p}.
The Euclidean Steinitz–Bergström theorem
TeX label cor:lp-steinitz, build/consequences.tex, line 9
The Lean statement says
theorem main : ∃ C : ℝ, SignedPrefixBound C ∧ OrderingPrefixBound C := by sorryA Lean statement states the theorem and leaves its proof as sorry on purpose. OpenAI’s proof is in a separate solution module, and a program called Comparator checks that proof against this statement.