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Regarding the question of how idempotent elements affect reversible property of rings, we study a version of reversibility depending on idempotents. In this perspective, we introduce {it right} (resp., {it left}) {it $e$-reversible rings}. We show that this concept is not left-right symmetric. Basic properties of right $e$-reversibility in a ring are provided. Among others it is proved that if $R$ is a semiprime ring, then $R$ is right $e$-reversible if and only if it is right $e$-reduced if and only if it is $e$-symmetric if and only if it is right $e$-semicommutative. Also, for a right $e$-reversible ring $R$, $R$ is a prime ring if and only if it is a domain. It is shown that the class of right $e$-reversible rings is strictly between that of $e$-symmetric rings and right $e$-semicommutative rings.
An ideal $I$ of a ring $R$ is called left N-reflexive if for any $ain$ nil$(R)$, $bin R$, being $aRb subseteq I$ implies $bRa subseteq I$ where nil$(R)$ is the set of all nilpotent elements of $R$. The ring $R$ is called left N-reflexive if the zero
We prove the main result that a groupoid of order n is an idempotent k-translatable quasigroup if and only if its multiplication is given by x.y = (ax+by)(mod n), where a+b = 1(mod n), a+bk = 0(mod n) and (k,n)= 1. We describe the structure of variou
In this paper we investigate the computational complexity of deciding if a given finite algebraic structure satisfies a fixed (strong) Maltsev condition $Sigma$. Our goal in this paper is to show that $Sigma$-testing can be accomplished in polynomial
We prove that one-step idempotent right modular groupoids are quasigroups. The dimension of such quasigroups is defined and all such quasigroups of dimensions 2,3 and 4 are determined.
Let $R$ be a commutative additively idempotent semiring. In this paper, some properties and characterizations for permanents of matrices over $R$ are established, and several inequalities for permanents are given. Also, the adjiont matrices of matrie