Some combinatorial problems in the theory of partial transformation semigroups
Vernadsky National Library of Ukraine
Переглянути архів Інформація| Поле | Співвідношення | |
| Title |
Some combinatorial problems in the theory of partial transformation semigroups
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| Creator |
Umar, A.
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| Description |
Let Xn = {1,2,…,n}. On a partial transformation α : Dom α ⊆ Xn → Im α ⊆ Xn of Xn the following parameters are defined: the breadth or width of α is ∣ Dom α ∣, the collapse of α is c(α) = ∣ ∪t∈Imα{tα⁻¹ :∣ tα⁻¹ ∣≥ 2} ∣, fix of α is f(α) = ∣ {x ∈ Xn : xα = x} ∣, the height of α is ∣ Imα ∣, and the right [left] waist of α is max(Imα) [min(Imα)]. The cardinalities of some equivalences defined by equalities of these parameters on Tn, the semigroup of full transformations of Xn, and Pn the semigroup of partial transformations of Xn and some of their notable subsemigroups that have been computed are gathered together and the open problems highlighted.
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| Date |
2019-06-10T11:03:52Z
2019-06-10T11:03:52Z 2014 |
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| Type |
Article
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| Identifier |
Some combinatorial problems in the theory of partial transformation semigroups / A. Umar // Algebra and Discrete Mathematics. — 2014. — Vol. 17, № 1. — С. 110–134. — Бібліогр.: 56 назв. — англ.
1726-3255 2010 MSC:20M17, 20M20, 05A10, 05A15. http://dspace.nbuv.gov.ua/handle/123456789/152350 |
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| Language |
en
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| Relation |
Algebra and Discrete Mathematics
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| Publisher |
Інститут прикладної математики і механіки НАН України
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