Release Time:2019-03-09  Hits:

Indexed by: Journal Article

Date of Publication: 2009-11-01

Journal: UTILITAS MATHEMATICA

Included Journals: Scopus、SCIE

Volume: 80

Page Number: 115-130

ISSN: 0315-3681

Key Words: extremal graph; forbidden subgraph

Abstract: Given a set of graphs Psi = {G(1), G(2), ... , G(k)}, let ex(n; Psi) denote the greatest size of a graph with order n that contains no subgraph isomorphic to any G(i), 1 <= i <= k. Clapham and Yang Yuansheng investigated the values of ex(n, Psi) for Psi = {C(4)}( Journal of Graph Theory, 13 (1989), 29-47 and Utilitas Mathematica, 41 (1992), 204-210) and ex(n, Psi) for Psi = {C(3), C(4), C(5)}(Utilitas Mathematica, 66 (2004), 249-265). Garnick investigated them for Psi = {C(3), C(4)} (Journal of Graph Theory, 17 (1993), 633-645). This paper investigates the values of ex (n, Psi) for Psi = {C(4), C(5)}, n <= 21.