A class of bisimple, idempotent-generated congruence-free semigroups
John M Howie · Proceedings of the Royal Society of Edinburgh Section A Mathematics · 1981
Synopsis Let X be a set with infinite regular cardinality m. Within the full transformation semigroup ℑ(X) a subsemigroup Sm is described which is bisimple and idempotent-generated. Its minimum non-trivial homomorphic image has both these properties and is also congruence-free. The semigroup contains an isomorphic copy of every semigroup having order less than m.