On the sum of orders of non-cyclic and non-normal subgroups in a finite group
Year 2024,
Volume: 36 Issue: 36, 206 - 214, 12.07.2024
Haowen Chen
Boru Zhang
Wei Meng
Abstract
Let $G$ be a finite group and $\mathcal{C}(G)$ denote the set of all non-normal non-cyclic subgroups of $G$. In this paper, the function $\delta_c(G) =\frac{1}{|G|}\sum\limits_{H\in\mathcal{C}(G)}|H|$ is introduced. In fact, we prove that, if $\delta_c(G)\leq \frac{10}{3}$, then either $G\cong A_5$, or $G$ is solvable. We also find some examples of finite groups $G$ with $\delta_c(G)\leq \frac{10}{3}$.
References
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V. A. Belonogov, Finite groups with three classes of maximal subgroups, Math. USSR-Sb., 59(1) (1988), 223-236.
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M. Brescia, M. Ferrara and M. Trombetti, The structure of metahamiltonian groups, Jpn. J. Math., 18(1) (2023), 1-65.
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L. Cui, W. Meng, J. Lu and W. Zheng, A new criterion for solvability of a finite group by the sum of orders of non-normal subgroups, Colloq. Math., 174(2) (2023), 169-176.
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R. Dedekind, Ueber Gruppen, deren sammtliche Theiler Normaltheiler sind, Math. Ann., 48 (1897), 548-561.
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X. Fang and L. An, A classification of finite metahamiltonian p-groups, Commun. Math. Stat., 9(2) (2021), 239-260.
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M. Garonzi and M. Patassini, Inequalities detecting structural properties of a finite group, Comm. Algebra, 45(2) (2017), 677-687.
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I. N. Herstein, A remark on finite groups, Proc. Amer. Math. Soc, 9(2) (1958), 255-257.
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M. Herzog, P. Longobardi and M. Maj, On a criterion for solvability of a finite group, Comm. Algebra, 49(5) (2021), 2234-2240.
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W. Meng and J. Lu, On the sum of non-cyclic subgroups order in a finite group, Comm. Algebra, 52(3) (2024), 1084-1096.
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M. Suzuki, Group Theory II, Fundamental Principles of Mathematical Sciences, 248, Springer-Verlag, New York, 1986.
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M. Tarnauceanu, Finite groups determined by an inequality of the orders of their subgroups II, Comm. Algebra, 45(11) (2017), 4865-4868.
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M. Tarnauceanu, On the solvability of a finite group by the sum of subgroup orders, Bull. Korean Math. Soc., 57 (2020), 1475-1479.
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M. Tarnauceanu, On the supersolvability of a finite group by the sum of subgroup orders, J. Algebra Appl., 21 (2022), 2250232 (7 pp).
Year 2024,
Volume: 36 Issue: 36, 206 - 214, 12.07.2024
Haowen Chen
Boru Zhang
Wei Meng
References
-
L. An and Q. Zhang, Finite metahamiltonian p-groups, J. Algebra, 442 (2015), 23-35.
-
V. A. Belonogov, Finite groups with three classes of maximal subgroups, Math. USSR-Sb., 59(1) (1988), 223-236.
-
M. Brescia, M. Ferrara and M. Trombetti, The structure of metahamiltonian groups, Jpn. J. Math., 18(1) (2023), 1-65.
-
L. Cui, W. Meng, J. Lu and W. Zheng, A new criterion for solvability of a finite group by the sum of orders of non-normal subgroups, Colloq. Math., 174(2) (2023), 169-176.
-
T. De Medts and M. Tarnauceanu, Finite groups determined by an inequality of the orders of their subgroups, Bull. Belg. Math. Soc. Simon Stevin, 15(4) (2008), 699-704.
-
R. Dedekind, Ueber Gruppen, deren sammtliche Theiler Normaltheiler sind, Math. Ann., 48 (1897), 548-561.
-
X. Fang and L. An, A classification of finite metahamiltonian p-groups, Commun. Math. Stat., 9(2) (2021), 239-260.
-
M. Garonzi and M. Patassini, Inequalities detecting structural properties of a finite group, Comm. Algebra, 45(2) (2017), 677-687.
-
I. N. Herstein, A remark on finite groups, Proc. Amer. Math. Soc, 9(2) (1958), 255-257.
-
M. Herzog, P. Longobardi and M. Maj, On a criterion for solvability of a finite group, Comm. Algebra, 49(5) (2021), 2234-2240.
-
W. Meng and J. Lu, On the sum of non-cyclic subgroups order in a finite group, Comm. Algebra, 52(3) (2024), 1084-1096.
-
M. Suzuki, Group Theory II, Fundamental Principles of Mathematical Sciences, 248, Springer-Verlag, New York, 1986.
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M. Tarnauceanu, Finite groups determined by an inequality of the orders of their subgroups II, Comm. Algebra, 45(11) (2017), 4865-4868.
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M. Tarnauceanu, On the solvability of a finite group by the sum of subgroup orders, Bull. Korean Math. Soc., 57 (2020), 1475-1479.
-
M. Tarnauceanu, On the supersolvability of a finite group by the sum of subgroup orders, J. Algebra Appl., 21 (2022), 2250232 (7 pp).