erdős #170 · sparse ruler problem
Let be the smallest possible size of such that . Find the value of
Worked, still open.
additive combinatorics · open · formalized (Lean) · 0 attempts
machinery: additive-combinatorics,Sidon/B_h,sieve/Brun-Titchmarsh,extremal-set-system
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vela registry pull vfr_37aec80d874a0239vela reproduce examples/erdos-problemsevidence
unverified AI candidates (2)
gpt-erdos · GPT-5.2 Pro + Deep Research · unverified
Because (N\in A-A) and (A\subset{0,1,\dots,N}), we must have (0\in A) and (N\in A) (the only way to get a difference of $N$ is $N-0$). So this is exactly the “complete sparse ruler of length $N$” problem. ([Wikipedia][1])
candidate solution ↗llm-hunter · gpt pro 5.2 · unverified
1 LLM attack(s) recorded (gpt pro 5.2); unverified.
candidate solution ↗formal
AMS 5 · api (literature)
lemma trivial_ruler_is_perfect (N : ℕ) : TrivialRuler N ∈ PerfectRulersLengthN Nformal-conjectures/170.lean ↗
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Sparse Ruler · reference
status
open