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arXiv · 1712.01920

Parity Factors I: General Kotzig-Lov\'asz Decomposition for Grafts

Nanao Kita
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Abstract

This paper is the first from a series of papers that establish a generalization of the basilica decomposition for cardinality minimum joins in grafts. Joins in grafts are also known as $T$-joins in graphs, where $T$ is a given set of vertices, and minimum joins in grafts can be considered as a generalization of perfect matchings in graphs provided in terms of parity. The basilica decomposition is a canonical decomposition applicable to general graphs with perfect matchings, and the general Kotzig-Lov\'asz decomposition is one of the three central concepts that compose this theory. The classical Kotzig-Lov\'asz decomposition is a canonical decomposition for a special class of graphs known as {\em factor-connected graphs} and is famous for its contribution to the study of the matching polytope and lattice. The general Kotzig-Lov\'asz decomposition is a nontrivial generalization of its classical counterpart and is applicable to general graphs with perfect matchings. As a component of the basilica decomposition theory, the general Kotzig-Lov\'asz decomposition has contributed to the derivation of further results in matching theory, such as a characterization of barriers or an alternative proof of the tight cut lemma. In this paper, we present an analogue of the general Kotzig-Lov\'asz decomposition for minimum joins in grafts.

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Nanao Kita. 2017-12-05. Parity Factors I: General Kotzig-Lov\'asz Decomposition for Grafts. https://arxiv.org/abs/1712.01920

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