All open problems
Source labels openChecked July 26, 2026

Green's Open ProblemsCombinatorics

Ben Green's Open Problem 16

From [Yufei Zhao]: Is there a subset of {1,,N}\{1, \ldots, N\} of size N1/3o(1)N^{1/3 - o(1)} with no nontrivial solutions to x+2y+3z=x+2y+3zx + 2y + 3z = x' + 2y' + 3z'?

Mathematical statement

From [Yufei Zhao]: Is there a subset of {1,,N}\{1, \ldots, N\} of size N1/3o(1)N^{1/3 - o(1)} with no nontrivial solutions to x+2y+3z=x+2y+3zx + 2y + 3z = x' + 2y' + 3z'?

Statement source: Green's Open 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

zhao_question

Canonical source
Complete statement target, proof intentionally absentLean 4
theorem zhao_question :    ¬∃ h :   , Tendsto h atTop (𝓝 0)  ᶠ N in atTop, (g N : )  (N : ) ^ (1 / 3 - h N) := 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