In this note, we derive an explicit formula for the equitable chromatic num
ber of a complete n-partite graph Kp(1),p(2),....,p(n). Namely, if M is the
largest integer such that
p(i) (mod M) < [pi/M] (i = 1, 2,...,n)
then
chie(Kp(1),p(2),...,p(n)) = Sigma (i=1 n) [pi/M + 1],
where chi (e)(G) is the equitable chromatic number of graph G. (C) 2001 Els
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