erdős #120 · Erdős similarity problem
Let be an infinite set. Must there be a set of positive measure which does not contain any set of the shape for some and ?
Worked, still open.
combinatorics · open · prize $100 · formalized (Lean) · 0 attempts
machinery: geometric,additive-combinatorics,Steinhaus-density,Erdos-similarity,measure-positive-set,affine-copy-avoidance
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unverified AI candidates (2)
gpt-erdos · GPT-5.2 Pro + Deep Research · unverified
Your question is exactly the **Erdős similarity problem / Erdős similarity conjecture**: an infinite set (A\subset\mathbb R) is called *universal (in measure)* if **every** measurable set (E\subset\mathbb R) with positive Lebesgue measure contains some nontrivial affine copy $aA+b$ [[nomath]](with $a\neq 0$)[[/nomath]]…
candidate solution ↗llm-hunter · gpt pro 5.2 · unverified
1 LLM attack(s) recorded (gpt pro 5.2); unverified.
candidate solution ↗formal
AMS 5 28 · open (literature)
theorem erdos_120 : answer(sorry) ↔ ∀ A : Set ℝ, A.Infinite → Erdos120For Aformal-conjectures/120.lean ↗
links
Green's open problems list · paper
status
open