Planar Digraphs of Digirth Five Are 2-Colorable

نویسندگان

  • Ararat Harutyunyan
  • Bojan Mohar
چکیده

Neumann-Lara (1985) and Škrekovski conjectured that every planar digraph with digirth at least three is 2-colorable, meaning that the vertices can be 2-colored without creating any monochromatic directed cycles. We prove a relaxed version of this conjecture: every planar digraph of digirth at least five is 2-colorable. The result also holds in the setting of list colorings.

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عنوان ژورنال:
  • Journal of Graph Theory

دوره 84  شماره 

صفحات  -

تاریخ انتشار 2017