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Let $p$ be a prime. Given any finite set $A\subseteq \mathbb{F}_p\backslash \{0\}$, is there always a rearrangement $A=\{a_1,\ldots,a_t\}$ such that all partial sums $\sum_{1\leq k\leq m}a_{k}$ are distinct, for all $1\leq m\leq t$?
A problem of Graham, who proved it when $t=p-1$. A similar conjecture was made for arbitrary abelian groups by Alspach. Such an ordering is often called a valid ordering.

This has been proved for $t\leq 12$ (see Costa and Pellegrini [CoPe20] and the references therein) and for $p-3\leq t\leq p-1$ (see Hicks, Ollis, and Schmitt [HOS19] and the references therein). Kravitz [Kr24] has proved this for \[t \leq \frac{\log p}{\log\log p}.\] (This was independently earlier observed by Will Sawin in a MathOverflow post.)

Bedert and Kravitz [BeKr24] have now proved this conjecture for \[t \leq e^{(\log p)^{1/4}}.\]

Additional thanks to: Zachary Chase and Noah Kravitz