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arXiv · 2406.13318

IBIS primitive groups of almost simple type

Fabio Mastrogiacomo·Pablo Spiga
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Abstract

Let $G$ be a finite permutation group on $\Omega$. An ordered sequence $(\omega_1\ldots,\omega_\ell)$ of elements of $\Omega$ is an irredundant base for $G$ if the pointwise stabilizer is trivial and no point is fixed by the stabilizer of its predecessors. The minimal cardinality of a base is said to be the base size of $G$. If all irredundant bases of $G$ have the same cardinality, $G$ is said to be an IBIS group. In this paper, we classify the finite almost simple primitive IBIS groups whose base size is at least $6$.

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Fabio Mastrogiacomo, Pablo Spiga. 2024-06-19. IBIS primitive groups of almost simple type. https://arxiv.org/abs/2406.13318

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