This paper provides a functional equation astisfied by the generating function for enumerating rooted loopless planar maps with vertex partition. A kind of applications in enumerating, by providing explicit formulae, ...This paper provides a functional equation astisfied by the generating function for enumerating rooted loopless planar maps with vertex partition. A kind of applications in enumerating, by providing explicit formulae, a type of rooted loopless planar maps with the maximum valency of vertices given are described. Meanwhile, the functional equation for enumerating rooted loopless planar maps (connected) with the edge number and the valency of root-vertex as the parameters is also derived directly.展开更多
The functional equation satisfied by the vertex partition function of rooted loopless Eulerianplanar maps is provided. As applications, the enumerating equations for general and regular casesof this kind of maps are a...The functional equation satisfied by the vertex partition function of rooted loopless Eulerianplanar maps is provided. As applications, the enumerating equations for general and regular casesof this kind of maps are also discussed.展开更多
On basis of two definitions that 1. an induced subgraph by a vertex vi E G and its neighbors in G is defined a vertex adjacent closed subgraph denoted by Qi (=G[V(Nvi)]), with the vertex vi called the hub; 2. A r...On basis of two definitions that 1. an induced subgraph by a vertex vi E G and its neighbors in G is defined a vertex adjacent closed subgraph denoted by Qi (=G[V(Nvi)]), with the vertex vi called the hub; 2. A r(k,1)-1 vertices connected graph is called a (k,l)-Ramsey graph denoted by RG(k,l),if and only if 1. RG(k,l) contains only cliques of degree k-1, and its complement contains only cliques of degree l-l; 2. the intersect Qi∩Qj of any two nonadjacent vertices vi and vj of RG(k,1) contains Kk.2, and the intersect Qi∩Qj of any two nonadjacent vertices vi and vj of its complement RG(l,k) contains KI.2. Two theorems that theoreml : the biggest clique in G is contained in some Qi of G, and theorem2: r(k,l)= [ V(RG(k,I)) I +1 are put forward and proved in this paper. With those definitions and theorems as well as analysis of property of chords a method for quick inspection and building RG(k,I) is proposed. Accordingly, RG(10,3) and its complement are built, which are respectively the strongly 29-regular graph and the strongly 10-regular graph on orders 40. We have tested RG(10,3) and its complement RG(3,10),and gotten r(3,10)=41.展开更多
基金This research was partially supported by the U. S. National Science Foundation under Grant Number ECS 85-03212 and by the National Natural Science Foundation of China as well. And, it was completed during the author's stay at RUTCOR, The State Univerity
文摘This paper provides a functional equation astisfied by the generating function for enumerating rooted loopless planar maps with vertex partition. A kind of applications in enumerating, by providing explicit formulae, a type of rooted loopless planar maps with the maximum valency of vertices given are described. Meanwhile, the functional equation for enumerating rooted loopless planar maps (connected) with the edge number and the valency of root-vertex as the parameters is also derived directly.
基金This project is supported partially by the National Natural Science Foundation of China Grant 18971061
文摘The functional equation satisfied by the vertex partition function of rooted loopless Eulerianplanar maps is provided. As applications, the enumerating equations for general and regular casesof this kind of maps are also discussed.
文摘On basis of two definitions that 1. an induced subgraph by a vertex vi E G and its neighbors in G is defined a vertex adjacent closed subgraph denoted by Qi (=G[V(Nvi)]), with the vertex vi called the hub; 2. A r(k,1)-1 vertices connected graph is called a (k,l)-Ramsey graph denoted by RG(k,l),if and only if 1. RG(k,l) contains only cliques of degree k-1, and its complement contains only cliques of degree l-l; 2. the intersect Qi∩Qj of any two nonadjacent vertices vi and vj of RG(k,1) contains Kk.2, and the intersect Qi∩Qj of any two nonadjacent vertices vi and vj of its complement RG(l,k) contains KI.2. Two theorems that theoreml : the biggest clique in G is contained in some Qi of G, and theorem2: r(k,l)= [ V(RG(k,I)) I +1 are put forward and proved in this paper. With those definitions and theorems as well as analysis of property of chords a method for quick inspection and building RG(k,I) is proposed. Accordingly, RG(10,3) and its complement are built, which are respectively the strongly 29-regular graph and the strongly 10-regular graph on orders 40. We have tested RG(10,3) and its complement RG(3,10),and gotten r(3,10)=41.