• theory, an inverse semigroup (occasionally called an inversion semigroup) S is a semigroup in which every element x in S has a unique inverse y in S in...
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  • inverse. If every element has exactly one inverse as defined in this section, then the semigroup is called an inverse semigroup. Finally, an inverse semigroup...
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  • Thumbnail for Semigroup
    we mention: regular semigroups, orthodox semigroups, semigroups with involution, inverse semigroups and cancellative semigroups. There are also interesting...
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  • an inverse semigroup, called the symmetric inverse semigroup (actually a monoid) on X. The conventional notation for the symmetric inverse semigroup on...
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  • group inverse. It is thus not a surprise that any group is a semigroup with involution. However, there are significant natural examples of semigroups with...
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  • the notion of regularity be applied to semigroups was first made by David Rees. The term inversive semigroup (French: demi-groupe inversif) was historically...
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  • the bicyclic semigroup is an inverse semigroup. (This means that each element x of B has a unique inverse y, in the "weak" semigroup sense that x y...
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  • mathematics, a semigroup is a nonempty set together with an associative binary operation. A special class of semigroups is a class of semigroups satisfying...
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  • X^{-1}})^{+}} we obtain a presentation (for an inverse semigroup) ( X ; T ) {\displaystyle (X;T)} and an inverse semigroup I n v ⟨ X | T ⟩ {\displaystyle \mathrm...
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  • mathematics, the term weak inverse is used with several meanings. In the theory of semigroups, a weak inverse of an element x in a semigroup (S, •) is an element...
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  • In algebra, a transformation semigroup (or composition semigroup) is a collection of transformations (functions from a set to itself) that is closed under...
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  • forms an important subclass of the class of regular semigroups, the class of inverse semigroups being another such subclass. Alfred H. Clifford was the...
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  • Nambooripad order (category Semigroup theory)
    e = ef = fe. Vagner in 1952 had extended this to inverse semigroups as follows: For any a and b in an inverse semigroup S, a ≤ b if and only if a = eb for some...
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  • matrices. Generalized inverses can be defined in any mathematical structure that involves associative multiplication, that is, in a semigroup. This article describes...
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  • mathematics, the Munn semigroup is the inverse semigroup of isomorphisms between principal ideals of a semilattice (a commutative semigroup of idempotents)...
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  • In mathematics, a catholic semigroup is a semigroup in which no two distinct elements have the same set of inverses. The terminology was introduced by...
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  • inverse may refer to: the inverse element in a group or in a subgroup of another, not necessarily group structure, e.g. in a subgroup of a semigroup the...
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  • symmetric semigroup (of all transformations) one also finds a weaker, non-unique notion of inverse (called a pseudoinverse) because the symmetric semigroup is...
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  • Clifford semigroup (sometimes also called "inverse Clifford semigroup") is a completely regular inverse semigroup. It is an inverse semigroup with x x...
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  • shown for inverse semigroups: every inverse semigroup admits an F-inverse cover. McAlister's covering theorem generalizes to orthodox semigroups: every orthodox...
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  • a regular semigroup that is also an E-semigroup is known as an orthodox semigroup. Weipoltshammer proved that the notion of weak inverse (the existence...
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  • Thumbnail for Generating set of a group
    slightly modified when one deals with semigroups or monoids. Indeed, this definition should not use the notion of inverse operation anymore. The set S {\displaystyle...
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  • In mathematics, a semigroup with no elements (the empty semigroup) is a semigroup in which the underlying set is the empty set. Many authors do not admit...
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  • all partial bijections on X {\displaystyle X} forms the symmetric inverse semigroup. Charts in the atlases which specify the structure of manifolds and...
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  • semigroup under this operation, the subsemigroup of idempotents being { a, b, c }. Inverse semigroups and bands are examples of orthodox semigroups....
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  • elements of S are inverses of each other. Nowhere commutative semigroups can be characterized in several different ways. If S is a semigroup then the following...
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  • 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 x, meaning that...
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  • Thumbnail for Quasigroup
    multiplicative inverse Semigroup – an algebraic structure consisting of a set together with an associative binary operation Monoid – a semigroup with an identity...
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  • transformation Unitary representation Unitarity (physics) E-unitary inverse semigroup Unitary authority Unitary state Unital (disambiguation) Unitarianism...
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  • = |x|). Monoid Inverse function Involution (mathematics) Multiplicative inverse Reflection (mathematics) Reflection symmetry Semigroup Gallian, Joseph...
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