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arXiv · 1811.07478

On a conjecture by Haipeng Qu

Marius Tărnăuceanu
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Abstract

In this note, we prove that $D_8\times C_2^{n-3}$ is the non-elementary abelian $2$-group of order $2^n$, $n\geq 3$, whose number of subgroups of possible orders is maximal. This solves a conjecture by Haipeng Qu [7]. A formula for counting the subgroups of an (almost) extraspecial $2$-group is also presented.

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Marius Tărnăuceanu. 2018-11-19. On a conjecture by Haipeng Qu. https://arxiv.org/abs/1811.07478

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