Circuit and fractional circuit covers of matroids

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Circuit and fractional circuit covers of matroids

LetM be a connectedmatroid having a ground set E. Lemos andOxley proved that |E(M)| ≤ 2 c(M)c (M)where c(M) (resp. c(M)) is the circumference (resp. cocircumference) of M. In addition, they conjectured that one can find a collection of at most c(M) circuits which cover the elements ofM at least twice. In this paper, we verify this conjecture for regular matroids. Moreover, we show that a versio...

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ژورنال

عنوان ژورنال: European Journal of Combinatorics

سال: 2010

ISSN: 0195-6698

DOI: 10.1016/j.ejc.2009.11.009