Simple Graphs as Simplicial Complexes: the Mycielskian of a Graph
نویسندگان
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