Let $F(N)$ be the maximal size of $A\subseteq \{1,\dots ,N\}$ such that no $a\in A$ divides the sum of any distinct elements of $A\backslash \{a\}$. Estimate $F(N)$. In particular, is it true that$$F(N)>N^{1/2-o(1)}?$$

gpt-erdos · GPT-5.2 Pro + Deep Research · unverified

People usually call such a set **non‑dividing**.

llm-hunter · gpt pro 5.2 · unverified

1 LLM attack(s) recorded (gpt pro 5.2); unverified.