chromatic and clique numbers of a class of perfect graphs
نویسندگان
چکیده
let $p$ be a prime number and $n$ be a positive integer. the graph $g_p(n)$ is a graph with vertex set $[n]={1,2,ldots ,n}$, in which there is an arc from $u$ to $v$ if and only if $uneq v$ and $pnmid u+v$. in this paper it is shown that $g_p(n)$ is a perfect graph. in addition, an explicit formula for the chromatic number of such graph is given.
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عنوان ژورنال:
transactions on combinatoricsناشر: university of isfahan
ISSN 2251-8657
دوره 4
شماره 4 2015
کلمات کلیدی
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