‎We characterize the finite simple groups $L_2(q)$ by the group orders and the largest‎ ‎element orders‎, ‎where $q$ is a prime or $q=2^a$‎, ‎with $2^a+1$ or $2^a-1$ a prime‎.  

let $g$ be a finite group‎. ‎we denote by $psi(g)$ the integer $sum_{gin g}o(g)$‎, ‎where $o(g)$ denotes the order of $g in g$‎. ‎here we show that‎ ‎$psi(a_5)< psi(g)$ for every non-simple group $g$ of order $60$‎, ‎where $a_5$ is the alternating group of degree $5$‎. ‎also we prove that $psi(psl(2,7))

let $g$ be a finite group‎. ‎we denote by $psi(g)$ the integer $sum_{gin g}o(g)$‎, ‎where $o(g)$ denotes the order of $g in g$‎. ‎here we show that‎ ‎$psi(a_5)< psi(g)$ for every non-simple group $g$ of order $60$‎, ‎where $a_5$ is the alternating group of degree $5$‎. ‎also we prove that $psi(psl(2,7))

in this paper, it is proved that all simple $k_4$-groups of type $l_2(q)$ can be characterized by their maximum element orders together with their orders. furthermore, the automorphism groups of simple $k_4$-groups of type $l_2(q)$ are also considered.

In this paper, it is proved that all simple $K_4$-groups of type $L_2(q)$ can be characterized by their maximum element orders together with their orders. Furthermore, the automorphism groups of simple $K_4$-groups of type $L_2(q)$ are also considered.

Given a rectangle A and a set S of n points in A, the maximum empty rectangle problem is that of finding a largest-area rectangle which is contained in A. has its sides parallel to Ihose ofA. and does Dot contain any of the points in S. This Dote describes an efficient algorithm for solving this problem.

Let G be a finite group , in this paper using the order and largest element order of G we show that every finite group with the same order and largest element order as G 2 (q), where q 11 is necessarily isomorphic to the group G 2 (q)

For a finite group [Formula: see text], let text] denote the sum of element orders text]. If is positive integer be cyclic order It known that maximum value on set groups and if only In this paper, we investigate second largest structure with when odd.

We describe an algorithm for selecting the n-th largest element (where 0 < < 1), from a totally ordered set of n elements, using at most (1 + (1 + o(1))H())n comparisons, where H() is the binary entropy function and the o(1) stands for a function that tends to 0 as tends to 0. For small values of this is almost the best possible as there is a lower bound of about (1 + H())n comparisons. The alg...