Simple Graphs as Simplicial Complexes: the Mycielskian of a Graph

نویسندگان

  • Piotr Rudnicki
  • Lorna Stewart
چکیده

Harary [10, p. 7] claims that Veblen [20, p. 2] first suggested to formalize simple graphs using simplicial complexes. We have developed basic terminology for simple graphs as at most 1-dimensional complexes. We formalize this new setting and then reprove Mycielski’s [12] construction resulting in a triangle-free graph with arbitrarily large chromatic number. A different formalization of similar material is in [15].

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عنوان ژورنال:
  • Formalized Mathematics

دوره 20  شماره 

صفحات  -

تاریخ انتشار 2012