Proofs and disproofs of some conjectures on zero-sum problems of new types

Yang Li, San Ling, Zhonghua Sun +1

For integers $r\ge 1$ and $n\ge 2$, let $s_r(n)$ be the least $N$ such that every sequence of $N$ vectors in ${\mathbb{Z}}^r$, each nonzero modulo $n$, contains $n$ terms whose sum is zero mod…