Cycle Cover Ratio of Regular Matroids

نویسندگان

  • Hong-Jian Lai
  • Hoifung Poon
چکیده

A cycle in a matroid is a disjoint union of circuits. This paper proves that every regular matroid M without coloops has a set S of cycles whose union is E(M) such that every element is in at most 3 of the cycles in S. It follows immediately from this that, on average, each element of M is in at most 3 members of the cycle cover S. This improves on a 1989 result of Jamshy and Tarsi who proved that there is a cycle cover for which this average is at most 4, and conjectured that a cycle cover exists for which the average is at most 2.

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عنوان ژورنال:
  • Eur. J. Comb.

دوره 23  شماره 

صفحات  -

تاریخ انتشار 2002