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arXiv · 1111.3061

Hultman numbers, polygon gluings and matrix integrals

Nikita Alexeev·Peter Zograf
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Abstract

The Hultman numbers enumerate permutations whose cycle graph has a given number of alternating cycles (they are relevant to the Bafna-Pevzner approach to genome comparison and genome rearrangements). We give two new interpretations of the Hultman numbers: in terms of polygon gluings and as integrals over the space of complex matrices, and derive some properties of their generating functions.

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Nikita Alexeev, Peter Zograf. 2011-11-13. Hultman numbers, polygon gluings and matrix integrals. https://arxiv.org/abs/1111.3061

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