Hajj Os Theorem for Colorings of Edge-weighted Graphs
نویسنده
چکیده
Hajj os theorem states that every graph with chromatic number at least k can be obtained from the complete graph K k by a sequence of simple operations such that every intermediate graph also has chromatic number at least k. Here, Hajj os theorem is extended in three slightly diierent ways to colorings and circular colorings of edge-weighted graphs. These extensions shed some new light on the Hajj os theorem and show that colorings of edge-weighted graphs are most natural extension of usual graph colorings.
منابع مشابه
Hajós Theorem For Colorings Of Edge-Weighted Graphs
Hajj os theorem states that every graph with chromatic number at least k can be obtained from the complete graph K k by a sequence of simple operations such that every intermediate graph also has chromatic number at least k. Here, Hajj os theorem is extended in three slightly diierent ways to colorings and circular colorings of edge-weighted graphs. These extensions shed some new light on the H...
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