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arXiv · 1109.0562

A tight bound on the length of odd cycles in the incompatibility graph of a non-C1P matrix

Mehrnoush Malekesmaeili·Cedric Chauve·Tamon Stephen
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Abstract

A binary matrix has the consecutive ones property (C1P) if it is possible to order the columns so that all 1s are consecutive in every row. In [McConnell, SODA 2004 768-777] the notion of incompatibility graph of a binary matrix was introduced and it was shown that odd cycles of this graph provide a certificate that a matrix does not have the consecutive ones property. A bound of (k+2) was claimed for the smallest odd cycle of a non-C1P matrix with k columns. In this note we show that this result can be obtained simply and directly via Tucker patterns, and that the correct bound is (k+2) when k is even, but (k+3) when k is odd.

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Mehrnoush Malekesmaeili, Cedric Chauve, Tamon Stephen. 2011-09-02. A tight bound on the length of odd cycles in the incompatibility graph of a non-C1P matrix. https://arxiv.org/abs/1109.0562

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