Chromatic Classes of 2-Connected (n, n+4)-Graphs with Exactly Three Triangles and at Least Two Induced 4-Cycles. (2nd November 2011)

• Record Type: Journal Article
• Authors: Lau Lau, G. C. G. C.; Peng Peng, Y. H. Y. H.
• Other Names: Isaak Isaak G. G. Academic Editor.
• Is Part Of: ISRN discrete mathematics. Volume 2011(2011)
• Publication Date: 2011-11-02
• Subjects: Discrete mathematics -- Periodicals; Computer science -- Mathematics; Computer science -- Mathematics; Periodicals; 511.1
• DOI: 10.5402/2011/430396
• Languages: English
• ISSNs: 2090-7788

Abstract

Abstract : For a graph G, let P ( G, λ ) be its chromatic polynomial. Two graphs G and H are chromatically equivalent, denoted G ~ H, if P ( G, λ ) = P ( H, λ ) . A graph G is chromatically unique if P ( H, λ ) = P ( G, λ ) implies that H ≅ G . In this paper, we determine all chromatic equivalence classes of 2-connected (n, n + 4 )-graphs with exactly three triangles and at least two induced 4-cycles. As a byproduct of these, we obtain various new families of χ -equivalent graphs and χ -unique graphs.