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arXiv · 2106.05821

An analogue of the strengthened Hanna Neumann conjecture for virtually free groups and virtually free products

Anton A. Klyachko·Alexander O. Zakharov
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Abstract

The Friedman--Mineyev theorem, earlier known as the (strengthened) Hanna Neumann conjecture, gives a sharp estimate for the rank of the intersection of two subgroups in a free group. We obtain an analogue of this inequality for any two subgroups in a virtually free group (or, more generally, in a group containing a free product of left-orderable groups as a finite-index subgroup).

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Anton A. Klyachko, Alexander O. Zakharov. 2021-06-10. An analogue of the strengthened Hanna Neumann conjecture for virtually free groups and virtually free products. https://doi.org/10.1307/mmj%2F20216105

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