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20182025
most citedOn certain semigroups of partial contractions of a finite chain

3 citations · 9 across the 10 of their papers we have counts for

collaborators

10 papers

math.GR2025

The monoid of monotone and decreasing partial transformations on a finite chain

Muhammad Mansur Zubairu, Abdullahi Umar, Fatma Salim Al-Kharousi

In this article, we consider the monoid of all monotone and order-decreasing partial transformations denoted as on an ordered chain ,…

math.GR2025

On the small Schröder semigroup

Muhammad Mansur Zubairu, Abdullahi Umar, Fatma Salim Al-Kharousi

Let be a finite chain , and let be the Schröder monoid, consisting of all isotone and order-decreasing partial transformations on $…

math.GR2024

On injective partial Catalan monoids

F. S. Al-Kharousi, A. Umar, M. M. Zubairu

Let be a finite chain , and let be the semigroup consisting of all isotone and order-decreasing injective partial transformations on $…

math.GR2024

On the algebraic structure of the Schröder monoid

Muhammad Mansur Zubairu, Abdullahi Umar, Fatma Salim Al-Kharousi

Let be a finite chain , and let be the semigroup consisting of all isotone and order-decreasing partial transformations on . More…

math.GR2022

On the Ranks of Semigroup of Order-preserving or Order-reversing Partial Contraction Mappings on a Finite Chain

B. Ali, M. A. Jada, M. M. Zubairu

Let be the semigroup of partial contraction mappings on and let and be its subsemigroups consisting of…

math.GR2022

On the combinatorial and rank properties of certain subsemigroups of full contractions of a finite chain

Muhammad Mansur Zubairu, Abdullahi Umar, Muhammad Jada Aliyu

Let be a finite chain and let be the semigroup of full contractions on . Denote and to be th…

math.GR2022★ 1 cited

On certain Semigroup of Order-decreasing Full Contraction Mappings of a Finite Chain

M. M. Zubairu, A. Umar, J. A. Aliyu

Let be the semigroup of full contraction mappings on , and let and be the subsemigroups consisting of al…

math.GR2018★ 2 cited

On certain semigroups of full contractions of a finite chain

A. Umar, M. M. Zubairu

Let be a finite chain and let be the semigroup of full transformations on . Let $\mathcal{CT}_{n}=\{α\in \mathcal{T}_{n}: (for ~all~x,…

math.GR2018★ 3 cited

On certain semigroups of partial contractions of a finite chain

A. Umar, M. M. Zubairu

Let be a finite chain and let be the semigroup of partial transformations on . Let $\mathcal{CP}_{n}=\{α\in \mathcal{P}_{n}: (for ~all…

math.GR2018★ 3 cited

Regularity and Green's relations for the semigroup of partial contractions of a finite chain

B. Ali, A. Umar, M. M. Zubairu

Let be a finite chain and let be the semigroup of partial transformations on . Let $\mathcal{CP}_{n}=\{α\in \mathcal{P}_{n}: (for~all…