Odd 2-factored snarks

نویسندگان

  • Marien Abreu
  • Domenico Labbate
  • Romeo Rizzi
  • John Sheehan
چکیده

A snark is a cubic cyclically 4–edge connected graph with edge chromatic number four and girth at least five. We say that a graph G is odd 2–factored if for each 2–factor F of G each cycle of F is odd. In this paper, we present a method for constructing odd 2–factored snarks. In particular, we construct two new odd 2–factored snarks that disprove a conjecture by some of the authors. Moreover, we approach the problem of characterizing odd 2–factored snarks furnishing a partial characterization of cyclically 4–edge connected odd 2–factored snarks. Finally, we pose a new conjecture regarding odd 2–factored snarks.

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عنوان ژورنال:
  • Eur. J. Comb.

دوره 36  شماره 

صفحات  -

تاریخ انتشار 2014