排序方式: 共有20条查询结果,搜索用时 15 毫秒
1.
数有根近2-正则平面地图 总被引:2,自引:0,他引:2
The number of rooted nearly 2-regular maps with the valency of root-vertex, the number of non-rooted vertices and the valency of root-face as three parameters is obtained. Furthermore, the explicit expressions of the special cases including loopless nearly 2-regular maps and simple nearly 2-regular maps in terms of the above three parameters are derived. 相似文献
2.
3.
4.
这篇文章得到了有根平面树的节点剖分的色和方程. 导出了带无限多个参数的有根平面植树和平面树的色和方程的精确表达式. 作为直接推论可推出节点剖分的有根平面树的计数方程的精确结果 . 相似文献
5.
In the present paper, a generalization of Steinhaus' chessboard problem of 8 × 8 and that of m×n are given and its solution is proved. Then, Steinhaus' chessboard problem is directly solved as a corollary, and the m>n case is solved immediately. 相似文献
6.
图G的顶点集V(G)的一个二部划分V_1和V_2叫做平衡二部划分,如果||V_1|-|V_2||≤1成立.Bollobas和Scott猜想:每一个有m条边且最小度不小于2的图,都存在一个平衡二部划分V_1,V_2,使得max{e(V_1),e(V_2)}≤m/3,此处e(V_i)表示两顶点都在V_i(i=1,2)中的边的条数.他们证明了这个猜想对正则图(即△(G)=δ(G))成立.颜娟和许宝刚证明了每个(k,k-1)-双正则图(即△(G)-δ(G)≤1)存在一个平衡二部划分V_1,V_2,使得每一顶点集的导出子图包含大约m/4条边.这里把该结论推广到最大度和最小度相差不超过2的图G. 相似文献
7.
8.
图在曲面上嵌入的分类就是确定图在同一曲面上(不等价的)嵌入的数目.本文,利用刘彦佩提出的嵌入的联树模型,得到了双极图与扇图的关联曲面之间的关系,进而由已知结论的双极图的亏格分布和完全亏格分布推导出扇图的亏格分布和完全亏格分布,并给出了扇图在亏格为1-4的不可定向曲面上嵌入的个数的显式. 相似文献
9.
10.
Enumeration of maps on the projective plane 总被引:1,自引:0,他引:1
1. IntroductionA lnap is rooted if an edge is distinguished togetl1er with an end and a side of the edge.An edge belo11ging to only one face is called double (or 8ingular by some author), al1 othersbelonging to exactly two faces are called s1ngle. The enumeration of rooted p1anar maps wasfirst introduced by Tutte['], Techniques originated by Tutte [2,3l for enumerating variousclasses of rooted Inaps on tIle sphere are here applied to the c1asses of alI rooted maps onthe projective plane. Th… 相似文献