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arXiv · 1304.0299

Amalgam width of matroids

Lukas Mach·Tomas Toufar
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Abstract

We introduce a new matroid width parameter based on the operation of matroid amalgamation, which we call amalgam-width. The parameter is linearly related to branch-width on finitely representable matroids (which is not possible for branch-width). In particular, any property expressible in the monadic second order logic can be decided in linear time for matroids with bounded amalgam-width. We also prove that the Tutte polynomial can be computed in polynomial time for matroids with bounded amalgam width.

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Lukas Mach, Tomas Toufar. 2013-04-01. Amalgam width of matroids. https://arxiv.org/abs/1304.0299

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