A short proof of Dirac's theorem on the number of edges in chromatically critical graphs
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چکیده
A short proof is presented for a theorem of G. A. Dirac (1974) giving a lower bound for the number of edges of a k-critical graph on a given number of vertices and describing all non-complete k-critical graphs with minimum edge excess.
منابع مشابه
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تاریخ انتشار 1996