An acyclic coloring of a graph G is a proper coloring of the vertex set of G such that G contains no bichromatic cycles. The acyclic chromatic number of a graph G is the minimum nu...
We examine designs and binary codes associated with the line graph of the n-cube Qn, i.e. the Hamming graph H(n, 2). We find the automorphism groups and the parameters of the cod...
Let a graph be locally disjoint union of three copies of complete graphs Kq-1 and let be cospectral with the Hamming graph H(3, q). Bang and Koolen [Asian-Eur. J. Math. 1 (2008),...
Average distance of a graph is expressed in terms of its canonical metric representation. The equality can be modified to an inequality in such a way that it characterizes isometr...