在S^1上n个开半圆的简单配置中,顶点的权是指包含它的半圆个数,可^表示权为k的顶点数,向量可=(v0,v1,…,vn-1)称为配置的可一向量.本文估算了伊向量对应的配置个数.
In an arrangement of n open semicircles on S^1 , the weight of a vertex is defined to be the number of semicircles containing it. The number of vertices having weight k is denoted by vk, v = (v0, v1,…,v._ 1) is called the v- vector of the arrangement. In this paper the number of different arrangements with a given v-vector is reckoned.