On two conjectures about the sum of element orders

نویسندگان

چکیده

Let $G$ be a finite group and $\psi(G) = \sum_{g \in G} o(g)$, where $o(g)$ denotes the order of $g G$. First, we prove that if is $n$ >31\psi(C_n)/77$, $C_n$ cyclic $n$, then supersolvable. This proves conjecture M.~{T\u{a}rn\u{a}uceanu}. Moreover, M. Herzog, P. Longobardi Maj put forward following conjecture: If $H\leq G$, \leqslant \psi(H) |G:H|^2$. In sequel, by an example show this not satisfied in general.

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ژورنال

عنوان ژورنال: Canadian mathematical bulletin

سال: 2021

ISSN: ['1496-4287', '0008-4395']

DOI: https://doi.org/10.4153/s0008439521000047