All open problems
Source labels openChecked July 26, 2026

WikipediaNumber theory

Büchi's problem

Büchi's problem* There exists a positive integer MM such that, for all integers xx and aa, if (x+n)2+a(x+n)^2 + a is a square for MM consecutive values of nn, then a=0a = 0.

Mathematical statement

Büchi's problem* There exists a positive integer MM such that, for all integers xx and aa, if (x+n)2+a(x+n)^2 + a is a square for MM consecutive values of nn, then a=0a = 0.

Statement source: Wikipedia statement material

Statement terms: CC-BY-SA-4.0

Attributed source material. Reuse must follow the linked attribution and share-alike terms.

Statement artifacts, not proofs

These records expose exact Lean propositions and statement-only wrappers. Defining a proposition does not supply a proof of it. A placeholder-bearing target also contains no proof. Elaboration checks syntax and types; it does not certify that a formalization perfectly captures every nuance of the informal problem.

Pinned Lean formulation 1

buchi_problem

Canonical source
Complete statement target, proof intentionally absentLean 4
theorem buchi_problem :    answer(sorry)   M : , 1  M  IsBuchi M := by  sorry
Statement source
Formal Conjectures
Lean version
v4.27.0
Placeholder
Present; no proof artifact
Source evidence
Pinned source index
Fidelity review
Community formulation

References