Published online by Cambridge University Press: 07 December 2020
One of the oldest outstanding problems in dynamical algebraic combinatorics is the following conjecture of P. Cameron and D. Fon-Der-Flaass (1995): consider a plane partition P in an $a \times b \times c$ box
${\sf B}$. Let
$\Psi (P)$ denote the smallest plane partition containing the minimal elements of
${\sf B} - P$. Then if
$p= a+b+c-1$ is prime, Cameron and Fon-Der-Flaass conjectured that the cardinality of the
$\Psi $-orbit of P is always a multiple of p.
This conjecture was established for $p \gg 0$ by Cameron and Fon-Der-Flaass (1995) and for slightly smaller values of p in work of K. Dilks, J. Striker and the second author (2017). Our main theorem specializes to prove this conjecture in full generality.