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arXiv · 1003.5782

Bricks and conjectures of Berge, Fulkerson and Seymour

Vahan Mkrtchyan·Eckhard Steffen
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Abstract

An $r$-graph is an $r$-regular graph where every odd set of vertices is connected by at least $r$ edges to the rest of the graph. Seymour conjectured that any $r$-graph is $r+1$-edge-colorable, and also that any $r$-graph contains $2r$ perfect matchings such that each edge belongs to two of them. We show that the minimum counter-example to either of these conjectures is a brick. Furthermore we disprove a variant of a conjecture of Fan, Raspaud.

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Vahan Mkrtchyan, Eckhard Steffen. 2010-03-30. Bricks and conjectures of Berge, Fulkerson and Seymour. https://arxiv.org/abs/1003.5782

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