Graph homomorphisms and chromatic numbers are foundational concepts in modern graph theory, with widespread applications that extend from combinatorial optimisation to theoretical computer science. A ...

This paper proves that for any integer n ≥ 4 and any rational number r, 2 ≤ r ≤ n — 2, there exists a graph G which has circular chromatic number r and which does not contain Kn as a minor. Journal ...

Vol. 12, No. 4, Dedicated to Professor Ko-Wei Lih on the Occasion of His 60th Birthday (July 2008), pp. 997-1005 (9 pages) The circular chromatic number χc(G) of a graph G is a very natural ...