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arXiv · 1409.0277

Regularity of powers of forests and cycles

Selvi Kara·Huy Tai Ha·Tran Nam Trung
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Abstract

Let G be a graph and let I = I(G) be its edge ideal. In this paper, when G is a forest or a cycle, we explicitly compute the regularity of I^s for all s > 0. In particular, for these classes of graphs, we provide the asymptotic linear function reg(I^s) as s > 0, and the initial value of s starting from which reg(I^s) attains its linear form. We also give new bounds on the regularity of I when G contains a Hamiltonian path and when G is a Hamiltonian graph.

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Selvi Kara, Huy Tai Ha, Tran Nam Trung. 2014-09-01. Regularity of powers of forests and cycles. https://arxiv.org/abs/1409.0277

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