PROVED
This has been solved in the affirmative.
Let $0<\epsilon<1$ and let $g_\epsilon(N)$ be the minimal $k$ such that if $G$ is an abelian group of size $N$ and $A\subseteq G$ is a uniformly random subset of size $k$, and\[F_A(g) = \#\left\{ S\subseteq A : g = \sum_{x\in S}x\right\},\]then, with probability $\to 1$ as $N\to \infty$,\[\left\lvert F_A(g)-\frac{2^k}{N}\right\rvert \leq \epsilon \frac{2^k}{N}\]for all $g\in G$.
Estimate $g_\epsilon(N)$ - in particular, is it true that for all $\epsilon>0$\[g_\epsilon(N)=(1+o_\epsilon(1))\log_2N?\]
It is trivial that $g_\epsilon(N)\geq \log_2N$ for all $0<\epsilon<1$. Erdős and Rényi
[ErRe65] proved that for all $0<\epsilon<1$\[g_\epsilon(N) \leq (2+o(1))\log_2N+O_\epsilon(1).\]Erdős and Hall
[ErHa76] proved that, for all $0<\epsilon<1$,\[g_\epsilon(N)\leq \left(1+O_\epsilon\left(\frac{\log\log\log N}{\log\log N}\right)\right)\log_2N.\]See also
[543].
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This page was last edited 26 January 2026.
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