Critical perfect graphs and perfect 3-chromatic graphs
نویسندگان
چکیده
منابع مشابه
chromatic and clique numbers of a class of perfect graphs
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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ژورنال
عنوان ژورنال: Journal of Combinatorial Theory, Series B
سال: 1977
ISSN: 0095-8956
DOI: 10.1016/0095-8956(77)90064-8