Abstract
Let[n] ={1,2, . . . , n} be a finite chain and let Pn (resp.,Tn) be the semigroup of partial transformations on[n] (resp., full transformations on[n]). Let CPn={α∈ Pn: (for allx, y ∈ Dom α)|xα−yα|⩽|x−y|}(resp., CTn={α∈ Tn: (for allx, y∈[n])|xα−yα|⩽|x−y|}) be the subsemigroup of partial contractionmappings on[n](resp., subsemigroup of full contraction mappingson[n]). We characterize all the starred Green’s relations on C Pn and it subsemigroup of order preserving and/or order reversingand subsemigroup of order preserving partial contractions on[n], respectively. We show that the semigroups CPn and CTn, and some of their subsemigroups are left abundant semigroups for all n but not right abundant forn⩾4. We further show that the set ofregular elements of the semigroup CTn and its subsemigroup of order preserving or order reversing full contractions on[n], each formsa regular subsemigroup and an orthodox semigroup, respectively.
Publisher
Luhansk Taras Shevchenko National University
Subject
Discrete Mathematics and Combinatorics,Algebra and Number Theory
Reference37 articles.
1. [1]A. El-Qallali, Structure theory for abundant and related semigroups. D. Phil. thesis, University of York, 1980.
2. [2]A. El-Qallali and J. B. Fountain, Quasi-adequate semigroups, Proc. Roy. Soc. Edinb. 91 A(1981), 91-99.
3. [3]A. H. Cliffoid and G. B. Preston: The algebraic theory of semigroups, 1 Math. Surveys of the American Math. Soc., 7, 1961.
4. [4]A. Umar, On the semigroups of order-decreasing finite full transformations, Proc. Roy. Soc. Edinb. Sect., A120(1992), no. 1-2, 129-142.
5. [5]A. Umar, On the semigroups of partial one-one order-decreasing finite transformations, Proc. Roy. Soc. Edinb. Sect., A123(1993), 355-363.
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