Achromatic Number of K 5 × K n for Small n
Mirko Horňák, Štefan Pčola · Czechoslovak Mathematical Journal · 2003
The achromatic number of a graph G is the maximum number of colours in a proper vertex colouring of G such that for any two distinct colours there is an edge of G incident with vertices of those two colours. We determine the achromatic number of the Cartesian product of K 5 and K n for all n ≤ 24.