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arXiv · 2410.17508

Validating a PTAS for Triangle-Free 2-Matching via a Simple Decomposition Theorem

Yusuke Kobayashi·Takashi Noguchi
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Abstract

A triangle-free (simple) 2-matching is an edge set that has at most $2$ edges incident to each vertex and contains no cycle of length $3$. For the problem of finding a maximum cardinality triangle-free 2-matching in a given graph, a complicated exact algorithm was proposed by Hartvigsen. Recently, a simple PTAS using local search was presented by Bosch-Calvo, Grandoni, and Ameli, but its validity proof is not easy. In this paper, we show a natural and simple decomposition theorem for triangle-free 2-matchings, which leads to a simpler validity proof of the PTAS for the problem.

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Yusuke Kobayashi, Takashi Noguchi. 2024-10-23. Validating a PTAS for Triangle-Free 2-Matching via a Simple Decomposition Theorem. https://arxiv.org/abs/2410.17508

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