In mathematics, a regular semigroup is a semigroup S in which every element is regular, i.e., for each element a in S there exists an element x in S such...

these we mention: regular semigroups, orthodox semigroups, semigroups with involution, inverse semigroups and cancellative semigroups. There are also interesting...

mathematics, particularly in abstract algebra, a semigroup with involution or a *-semigroup is a semigroup equipped with an involutive anti-automorphism...

completely regular semigroup is a semigroup in which every element is in some subgroup of the semigroup. The class of completely regular semigroups forms an...

mathematics, a semigroup is a nonempty set together with an associative binary operation. A special class of semigroups is a class of semigroups satisfying...

an I-semigroup and a *-semigroup. A class of semigroups important in semigroup theory are completely regular semigroups; these are I-semigroups in which...

In mathematics, the bicyclic semigroup is an algebraic object important for the structure theory of semigroups. Although it is in fact a monoid, it is...

that x = xyx and y = yxy, i.e. a regular semigroup in which every element has a unique inverse. Inverse semigroups appear in a range of contexts; for...

In algebra, a transformation semigroup (or composition semigroup) is a collection of transformations (functions from a set to itself) that is closed under...

Neumann regular ring, or absolutely flat ring (unrelated to the previous sense) Regular semi-algebraic systems in computer algebra Regular semigroup, related...

mathematics, the four-spiral semigroup is a special semigroup generated by four idempotent elements. This special semigroup was first studied by Karl Byleen...

a semigroup. The set of idempotents in a semigroup is a biordered set and every biordered set is the set of idempotents of some semigroup. A regular biordered...

Neumann regular rings include π-regular rings, left/right semihereditary rings, left/right nonsingular rings and semiprimitive rings. Regular semigroup Weak...

orthodox semigroup is a regular semigroup whose set of idempotents forms a subsemigroup. In more recent terminology, an orthodox semigroup is a regular E-semigroup...

Nambooripad's partial order) is a certain natural partial order on a regular semigroup discovered by K S S Nambooripad in late seventies. Since the same...

on a given base set, together with function composition, forms a regular semigroup. For a finite set of cardinality n, there are nn transformations and...

regular. A regular semigroup is a semigroup in which every element is regular. This is a stronger notion than weak inverse. Every regular semigroup is...

quasi-periodic semigroup, group-bound semigroup, completely π-regular semigroup, strongly π-regular semigroup (sπr), or just π-regular semigroup (although...

In abstract algebra, an E-dense semigroup (also called an E-inversive semigroup) is a semigroup in which every element a has at least one weak inverse...

or occasionally as the full linear semigroup or general linear monoid. Notably, it constitutes a regular semigroup. If one removes the restriction of...

In abstract algebra, a Moore–Penrose inverse may be defined on a *-regular semigroup. This abstract definition coincides with the one in linear algebra...

published in 1979. Every catholic semigroup either is a regular semigroup or has precisely one element that is not regular, much like the partitioners of...

inverse (called a pseudoinverse) because the symmetric semigroup is a regular semigroup. If Y ⊆ X, then f : X → Y {\displaystyle f:X\to Y} may compose with...

In mathematics, a band (also called idempotent semigroup) is a semigroup in which every element is idempotent (in other words equal to its own square)...

mathematical structure that involves associative multiplication, that is, in a semigroup. This article describes generalized inverses of a matrix A {\displaystyle...

{\displaystyle X,} forms a regular semigroup called the semigroup of all partial transformations (or the partial transformation semigroup on X {\displaystyle...

theory of semigroups. Vol. 2, American Mathematical Society Clifford, Alfred. H. (1974), The Partial Groupoid of Idempotents of a Regular Semigroup, Tulane...

transformation semigroup is a regular semigroup. g {\displaystyle g} acts as a (not necessarily unique) quasi-inverse for f; within semigroup theory this...

who has made fundamental contributions to the structure theory of regular semigroups. Nambooripad was also instrumental in popularising the TeX software...

Rees matrix semigroups are a special class of semigroups introduced by David Rees in 1940. They are of fundamental importance in semigroup theory because...