Recognition by degree prime-power graph and order of some characteristically simple groups

Document Type : Original Article

Authors

Department of Mathematics and Computer Science, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran

Abstract

In this paper, by the order of a group and triviality of $O_p(G)$ for some prime $p$, we give a new characterization for some characteristically simple groups. In fact, we prove that if {$p \in \{5, 17, 23, 37, 47, 73\}$ and $n \leqslant p$, where $n$ is a natural number, then $G\cong{{\rm PSL}(2,p)}^{n}$ if and only if $ |G|=|{{\rm PSL}(2,p)}|^{n}$ and $O_p(G)=1$. Recently in [Qin, Yan, Shum and Chen, Comm. Algebra, 2019], the degree prime-power graph of a finite groupb have been introduced and it is proved that the Mathieu groups are uniquely determined by their degree prime-power graphs and orders. As a consequence of our results, we show that ${\rm PSL}(2,p)^n$, where $p\in\{5,17,23,37,47,73\}$ and $n\leqslant{p}$ are uniquely determined by their degree prime-power graphs and orders.

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[1] M. Baniasad Azad, B. Khosravi, Recognition of some characteristically simple groups by their complex group algebra, Math. Rep (to appear).
[2] I. M. Isaacs, Character theory of finite groups, Academic Press, New York, 1976.
[3] P. Hall, A contribution to the theory of groups of prime power order, Proc. London Math. Soc., 36 (1933) 29-95.
[4] M. Khademi, B. Khosravi, Recognition of characteristically simple group A5 × A5 by character degree graph and order, Czechoslovak Math. J., 68 (143) (2018) 1149-1157.
[5] B. Khosravi, B. Khosravi, B. Khosravi, Z. Momen, Recognition by character degree graph and order of the simple groups of order less than 6000, Miskolc Math. Notes, 15 (2) (2014) 537-544.
[6] B. Khosravi, B. Khosravi, B. Khosravi, Z. Momen, Recognition by character degree graph and order of some simple groups, Math. Rep, 18 (68) (2016) 130-137.
[7] M. L. Lewis, An overview of graphs associated with character degrees and conjugacy class sizes in finite groups, Rocky Mt. J. Math., 38 (1) (2008) 175-211.
[8] O. Manz, R. Staszewski, W. Willems, On the number of components of a graph related to character degrees, Proc. Amer. Math. Soc., 103 (1) (1988) 31-37.
[9] M. B. Nathanson, Elementary Methods in Number Theory, Springer edition, NewYork, 2000.
[10] C. Qin, Y. Yan, K. P. Shum, G. Y. Chen, Mathieu groups and its degree prime-power graphs, Commun. Algebra, 47 (10) (2019) 4173-4180.
[11] H. Xu, G. Y. Chen, Y. Yan, A new characterization of simple K3-groups by their orders and large degrees of their irreducible characters, Commun. Algebra, 42 (2014) 5374-5380.
[12] A. V. Zavarnitsine, Finite simple groups with narrow prime spectrum, Sib. Elektron. Mat. Izv 6 (2009) 1-12.