Characterization of Uniquely Colorable and Perfect Graphs
نویسندگان
چکیده
This paper studies the concepts of uniquely colorable graphs & Perfect graphs. The main results are 1) Every uniquely k-colorable graph is (k 1)-connected. 2) If G is a uniquely k-colorable graph, then (G) ≥ k l. 3) A maximal planar graph G of order 3 or more has chromatic number 3 if and only if G is Eulerian. 4) Every interval graph is perfect. 5) A graph G is chordal if and only if G can be obtained by identifying two complete. Sub graphs if the same order in two chordal graphs. Mathematics Subject Classification 2000: 05CXX, 05C15, 05C20, 37E25.
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