From the 1 of 9 linked papers with an AI index.
9 papers
Involutions of (twisted) diagram monoids
James East, P. A. Azeef Muhammed
The paper classifies all involutions of several well-known diagram monoids and their twisted versions, and determines which involutions give rise to star‑regular or regular star‑mo…
Twisted products of monoids
James East, Robert D. Gray, P. A. Azeef Muhammed +1
A twisting of a monoid is a map satisfying the identity . Together with an additive commutative monoid ,…
Maximal subgroups of free projection- and idempotent-generated semigroups with applications to partition monoids
James East, Robert D. Gray, P. A. Azeef Muhammed +1
This paper investigates the maximal subgroups of a free projection-generated regular -semigroup over a projection algebra , and their relationship to the maximal subg…
Projection algebras and free projection- and idempotent-generated regular -semigroups
James East, Robert D. Gray, P. A. Azeef Muhammed +1
The purpose of this paper is to introduce a new family of semigroups - the free projection-generated regular -semigroups - and initiate their systematic study. Such a semigroup…
Heights of one- and two-sided congruence lattices of semigroups
M. Brookes, J. East, C. Miller +2
The height of a poset is the supremum of the cardinalities of chains in . The exact formula for the height of the subgroup lattice of the symmetric group is…
Categorical representation of DRC-semigroups
James East, Matthias Fresacher, P. A. Azeef Muhammed +1
DRC-semigroups model associative systems with domain and range operations, and contain many important classes, such as inverse, restriction, Ehresmann, regular -, and -regula…