NEW BOUNDS FOR THE CLIQUE-CHROMATIC NUMBERS OF JOHNSON’S GRAPHS
We significantly improve lower bounds on clique-chromatic numbers for some families of Johnson graphs. We also obtain a new upper bound on clique-chromatic number for G(n, r, r – 1) and G(n, 3, 1). Finally, we provide the exact value of clique-chromatic number G(n, 2, 1).