2 papers
math.RA2023
Finite Presentability of Brin-Higman-Thompson Monoids via Free Jónsson-Tarski Algebras
Bill de Witt, Luna Elliott
We show that the monoids totM_{k,1} introduced by Birget and their generalizations tot nM_{k,r} which extend the Brin-Higman-Thompson groups, can be realized as the endomorphism mo…
math.RA2021
On the number of countable subdirect powers of unary algebras
Nik Ruskuc, Bill de Witt
A finite unary algebra has only countably many countable subdirect powers if and only if every operation is either a permutation or a constant mapping.