Two Results on Real Zeros of Chromatic Polynomials

This note presents two results on real zeros of chromatic polynomials. The first result states that if G is a graph containing a q-tree as a spanning subgraph, then the chromatic polynomial P(G, ) of G has no non-integer zeros in the interval (0, q). Sokal conjectured that for any graph G and any real > (G), P(G, ) > 0. Our second result confirms that it is true if (G) n/3 - 1, where n is the order of G.

• Type: Journal
• Year: 2004
• Where: CPC
• Authors: Feng Ming Dong, Khee Meng Koh
• Keywords: Chromatic Polynomial, CPC 2004, Non-integer Zeros, Real Zeros