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Source labels openChecked July 26, 2026

Erdős ProblemsNumber theory

Erdős Problem 850

Can there exist two distinct integers xx and yy such that x,yx,y have the same prime factors, x+1,y+1x+1,y+1 have the same prime factors, and x+2,y+2x+2,y+2 also have the same prime factors?

Mathematical statement

Can there exist two distinct integers xx and yy such that x,yx,y have the same prime factors, x+1,y+1x+1,y+1 have the same prime factors, and x+2,y+2x+2,y+2 also have the same prime factors?

Statement source: Erdős Problems statement material

Statement terms: Source-specific

Source-specific terms. Therefore does not assert reuse rights beyond attributed display.

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

erdos_850

Canonical source
Complete statement target, proof intentionally absentLean 4
theorem erdos_850 :    answer(sorry)   x y : , x  y  x.primeFactors = y.primeFactors       (x + 1).primeFactors = (y + 1).primeFactors       (x + 2).primeFactors = (y + 2).primeFactors := 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