All open problems
Source labels openChecked July 26, 2026

Erdős ProblemsCombinatorics

Erdős Problem 153

Let AA be a finite Sidon set and A+A={s1<<st}A+A=\{s_1<\cdots<s_t\}. Is it true that 1t1i<t(si+1si)2\frac{1}{t}\sum_{1\leq i<t}(s_{i+1}-s_i)^2 \to \infty as A\lvert A\rvert\to \infty?

Mathematical statement

Let AA be a finite Sidon set and A+A={s1<<st}A+A=\{s_1<\cdots<s_t\}. Is it true that 1t1i<t(si+1si)2\frac{1}{t}\sum_{1\leq i<t}(s_{i+1}-s_i)^2 \to \infty as A\lvert A\rvert\to \infty?

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_153

Canonical source
Complete statement target, proof intentionally absentLean 4
theorem erdos_153 : answer(sorry)  Tendsto f atTop atTop := 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