一类图构形的Orlik-Solomon代数及Tutte多项式

研究得到了n-秩轮图及其导出图构形的Orlik-Solomon代数的计算公式，n-秩轮图关于某条边的删除B_n以及n-秩轮图的Tutte多项式的一般表达式，并计算了n-秩轮图（n=5，6）的双变量着色多项式，举例说明图的双变量着色多项式与Tutte多项式是不相同的。

Orlik-Solomon algebra and Tutte polynomials of a class of graphic arrangements

We study a special class of graphic arrangements, the hyperplane arran gement associated with an n-rank wheel graph. Firstly, we prove formulae for the dimensions of the Orlik-Solomon algebra of the graphic arrangements associated with the n-rank wheel graph and other graphs related to it. Secondly, we compute Tutte polynomials of the n-rank wheel graph and graphs obtained from the n-rank wheel graph by deleting a boundary edge, and obtain general formulae. Finally, we study two-variable chromatic polynomials for an n-rank wheel graph and show that this polynomial is different from the Tutte polyn omial.