let g be a group. a subset x of g is a set of pairwise noncommuting elements if xy ̸= yx for any two distinct elements x and y in x. if |x| ≥ |y | for any other set of pairwise non-commuting elements y in g, then x is said to be a maximal subset of pairwise non-commuting elements. in this paper we determine the cardinality of a maximal subset of pairwise non-commuting elements in any non-abelian...

A b s t r a c t. In this paper we characterize, classify and axiomatize all axiomatic extensions of the Nilpotent Minimum Logic. Every axiomatic extension is complete with respect to a class of NM-chains. Given a family of NM-chains the number of elements of the largest odd finite NM-chain in the family and the number of elements of the largest even finite NM-chain in the family turns out to be...

The present study involves the flora of the Estil wetland and its surroundings in Astara, northwest Iran. During 2006-07, we examined the plant specimens collected in this area and determined that there are 247 vascular plant taxa (229 species, 11 subspecies, and seven varieties) in 170 genera and 60 families. The largest families are Poaceae (27 taxa), Asteraceae (26), and Brassicaceae (21). G...

let $g$ be a group and $pi(g)$ be the set of primes $p$ such that $g$ contains an element of order $p$. let $nse(g)$ be the set of the number of elements of the same order in $g$. in this paper, we prove that the simple group $l_2(p^2)$ is uniquely determined by $nse(l_2(p^2))$, where $pin{11,13}$‎.‎