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Counting cocircuits and convex two-colourings is #P-complete

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 Added by Steven Noble
 Publication date 2008
and research's language is English




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We prove that the problem of counting the number of colourings of the vertices of a graph with at most two colours, such that the colour classes induce connected subgraphs is #P-complete. We also show that the closely related problem of counting the number of cocircuits of a graph is #P-complete.

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103 - Richard Lang , Maya Stein 2015
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