3 problems

Let $S$ be a finite commutative semigroup, let $K$ be a field, and let $\Gamma(H_a)$ denote the group associated with the $\mathcal H$-class of $a$. Write … Here $\bar a$ is the im…

Finiteness conjecture. If $d(S,R)<\infty$, then the displayed supremum is finite. This proposes a necessary condition complementing the preceding sufficient criterion for finitenes…

Let ${\rm C}_{k;n}$ be a cyclic commutative semigroup with parameters $k$ and $n$, and let ${\hat{\sl l}}({\rm C}_{k;n})$ denote the threshold associated with idempotent-sum-free s…