2连通的(n,n+4)图是有n个顶点n+4条边的连通图,利用图的色多项式理论研究了两类2连通的(n,n+4)图的色性,由此部分或完全解决了图G5和图G12的色唯一性问题.
2-connected ( n, n + 4) graphs are the connected graphs with order n and size n + 4. By the theory of chromatic polynomials of graphs, the chromaticity of two classes of 2-connected (n, n + 4) graphs are studied. Then the chromatic uniqueness of graphs G5 and G12 is partially and completely solved, respectively.