Independence, irredundance, degrees and chromatic number in graphs
نویسندگان
چکیده
منابع مشابه
Independence, irredundance, degrees and chromatic number in graphs
Let (G) and IR(G) denote the independence number and the upper irredundance number of a graph G. We prove that in any graph of order n, minimum degree and maximum degree =0, IR(G)6 n=(1 + = ) and IR(G) − (G)6 (( − 2)=2 )n. The two bounds are attained by arbitrarily large graphs. The second one proves a conjecture by Rautenbach related to the case = 3. When the chromatic number of G is less than...
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ژورنال
عنوان ژورنال: Discrete Mathematics
سال: 2002
ISSN: 0012-365X
DOI: 10.1016/s0012-365x(02)00585-x