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Infinitude of Wall–Sun–Sun primes

A prime pp is a Wall–Sun–Sun prime if and only if Lp1(modp2)L_p \equiv 1 \pmod{p^2}, where LpL_p is the pp-th Lucas number. It is conjectured that there are infinitely many Wall-Sun-Sun primes.

Mathematical statement

A prime pp is a Wall–Sun–Sun prime if and only if Lp1(modp2)L_p \equiv 1 \pmod{p^2}, where LpL_p is the pp-th Lucas number. It is conjectured that there are infinitely many Wall-Sun-Sun primes.

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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

infinite_isWallSunSunPrime

Canonical source
Complete statement target, proof intentionally absentLean 4
theorem infinite_isWallSunSunPrime : {p :  | IsWallSunSunPrime p}.Infinite := 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