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Erdős ProblemsNumber theory

Erdős Problem 695: Upper Bound

Is there a sequence of primes q1<q2<q_1 < q_2 < \cdots such that qi+11(modqi)q_{i + 1} \equiv 1 \pmod{q_i} and q(k)exp(k(logk)1+o(1))?q(k) \leq \exp(k (\log k)^{1 + o(1)})?

Mathematical statement

Is there a sequence of primes q1<q2<q_1 < q_2 < \cdots such that qi+11(modqi)q_{i + 1} \equiv 1 \pmod{q_i} and

q(k)exp(k(logk)1+o(1))?q(k) \leq \exp(k (\log k)^{1 + o(1)})?

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_695.variants.upperBound

Canonical source
Complete statement target, proof intentionally absentLean 4
theorem erdos_695.variants.upperBound : answer(sorry)      q :   ,      StrictMono q       ( i, (q i).Prime)       ( i, q (i + 1) % q i = 1)        o :   ,        (o =o[atTop] (1 :   ))         -- We use `(k + 1)` here as the informal statement is 1-indexed.         k, q k  exp ((k + 1) * log (k + 1) ^ (1 + o k)) := 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