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BooksNumber theory

Bugeaud Collection of Conjectures and Open Questions: Rapidly Increasing Sequences Dense Modulo One

Problem 10.6. Find a very rapidly increasing sequence (mn)n1(m_n)_{n \ge 1} of positive integers such that ({ξmn})n1(\{\xi m_n\})_{n \ge 1} is dense modulo one for every irrational number ξ\xi. Note: Furstenberg's 2m3n2^m3^n is sublacunary but requires two parameters.

Mathematical statement

Problem 10.6. Find a very rapidly increasing sequence (mn)n1(m_n)_{n \ge 1} of positive integers such that ({ξmn})n1(\{\xi m_n\})_{n \ge 1} is dense modulo one for every irrational number ξ\xi. Note: Furstenberg's 2m3n2^m3^n is sublacunary but requires two parameters.

Statement source: Books 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

problem_10_6_variant_1

Canonical source
Complete statement target, proof intentionally absentLean 4
theorem problem_10_6_variant_1 :     m :   ,    StrictMono m     IsGenuinelySublacunary m      ξ : , Irrational ξ       Dense (Set.range fun n => (↑(ξ * m n) : AddCircle (1 : ))) := 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