Chromatic-index critical multigraphs of order 20

نویسنده

  • Stefan Grünewald
چکیده

A multigraph M with maximum degree (M) is called critical, if the chromatic index 0 (M) > (M) and 0 (M ? e) = 0 (M) ? 1 for each edge e of M. The weak critical graph conjecture 1, 7] claims that there exists a constant c > 0 such that every critical multigraph M with at most c (M) vertices has odd order. We disprove this conjecture by constructing critical multigraphs of order 20 with maximum degree k for all k 5.

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عنوان ژورنال:
  • Journal of Graph Theory

دوره 33  شماره 

صفحات  -

تاریخ انتشار 2000