Abstract:
In this talk we will introduce some new problems and related
progress on determinants involving Legendre symbols, circular
permutations and additive combinatorics. For example, we conjecture
that for any finite subset $A$ of an additive cyclic group $G$ with
$|A|=n>3$ there is a circular permutation $a_1,\ldots,a_n$ of the
elements of $A$ such that all the $n$ sums
$$a_1+a_2+a_3, a_2+a_3+a_4,\ldots, a_{n-2}+a_{n-1}+a_n,
a_{n-1}+a_n+a_1, a_n+a_1+a_2$$
are pairwise distinct. The speaker has proved this when
$G$ is the infinite cyclic group $\mathbb Z$.