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1.
Let G be a simple graph.An IE-total coloring f of G refers to a coloring of the vertices and edges of G so that no two adjacent vertices receive the same color.Let C(u) be the set of colors of vertex u and edges incident to u under f.For an IE-total coloring f of G using k colors,if C(u)=C(v) for any two different vertices u and v of V(G),then f is called a k-vertex-distinguishing IE-total-coloring of G,or a k-VDIET coloring of G for short.The minimum number of colors required for a VDIET coloring of G is denoted by χ ie vt (G),and it is called the VDIET chromatic number of G.We will give VDIET chromatic numbers for complete bipartite graph K4,n (n≥4),K n,n (5≤ n ≤ 21) in this article.  相似文献   

2.
Let G be a simple graph. An IE-total coloring f of G refers to a coloring of the vertices and edges of G so that no two adjacent vertices receive the same color. Let C(u) be the set of colors of vertex u and edges incident to u under f. For an IE-total coloring f of G using k colors, if C(u)=C(v) for any two different vertices u and v of V (G), then f is called a k-vertex-distinguishing IE-total-coloring of G, or a k-VDIET coloring of G for short. The minimum number of colors required for a VDIET coloring of G is denoted by χievt(G), and is called the VDIET chromatic number of G. We get the VDIET chromatic numbers of cycles and wheels, and propose related conjectures in this paper.  相似文献   

3.
Let G be a simple graph.An IE-total coloring f of G refers to a coloring of the vertices and edges of G so that no two adjacent vertices receive the same color.Let C(u) be the set of colors of vertex u and edges incident to u under f.For an IE-total coloring f of G using k colors,if C(u)=C(v) for any two different vertices u and v of V(G),then f is called a k-vertex-distinguishing IE-total-coloring of G,or a k-VDIET coloring of G for short.The minimum number of colors required for a VDIET coloring of G is denoted by χ ie vt (G),and it is called the VDIET chromatic number of G.We will give VDIET chromatic numbers for complete bipartite graph K4,n (n≥4),K n,n (5≤ n ≤ 21) in this article.  相似文献   

4.
Let G be a simple graph of order at least 2.A VE-total-coloring using k colors of a graph G is a mapping f from V (G) E(G) into {1,2,···,k} such that no edge receives the same color as one of its endpoints.Let C(u)={f(u)} {f(uv) | uv ∈ E(G)} be the color-set of u.If C(u)=C(v) for any two vertices u and v of V (G),then f is called a k-vertex-distinguishing VE-total coloring of G or a k-VDVET coloring of G for short.The minimum number of colors required for a VDVET coloring of G is denoted by χ ve vt (G) and it is called the VDVET chromatic number of G.In this paper we get cycle C n,path P n and complete graph K n of their VDVET chromatic numbers and propose a related conjecture.  相似文献   

5.
设f是图G的一个正常全染色.对任意x∈V(G),令C(x)表示与点x相关联或相邻的元素的颜色以及点x的颜色所构成的集合.若对任意u,v∈V(G),u≠v,有C(u)≠C(v),则称.f是图G的一个点强可区别全染色,对一个图G进行点强可区别全染色所需的最少的颜色的数目称为G的点强可区别全色数,记为X_(vst)(G).讨论了完全二部图K_(1,n),K_(2,n)和L_(3,n)的点强可区别全色数,利用组合分析法,得到了当n≥3时,X_(vst)(K_(1,n)=n+1,当n≥4时,X_(vst)(K_(2,n)=n+2,当n≥5时,X_(vst)(K_(3,n))=n+2.  相似文献   

6.
若图的邻点可区别全染色的各色所染元素数之差不超过1,则称该染色法为图的均匀邻点可区别全染色,而所用的最少颜色数称为该图的均匀邻点可区别全色数.本文给出了一类二部图的均匀邻点可区别全染色数.  相似文献   

7.
Let be a function on the vertex set of the graph . The graph G is f‐choosable if for every collection of lists with list sizes specified by f there is a proper coloring using colors from the lists. The sum choice number, , is the minimum of , over all functions f such that G is f‐choosable. It is known (Alon, Surveys in Combinatorics, 1993 (Keele), London Mathematical Society Lecture Note Series, Vol. 187, Cambridge University Press, Cambridge, 1993, pp. 1–33, Random Struct Algor 16 (2000), 364–368) that if G has average degree d, then the usual choice number is at least , so they grow simultaneously. In this article, we show that can be bounded while the minimum degree . Our main tool is to give tight estimates for the sum choice number of the unbalanced complete bipartite graph .  相似文献   

8.
马刚  马少仙  覃正辉 《数学研究》2010,43(2):206-210
文献【2】定义点可区别全染色,对—个图其所用最少染色数称为它的点可区别全色数.本文得到了星、扇和轮的Double图的点可区别全色数.  相似文献   

9.
图G的一个k-正常边染色f被称为点可区别边染色是指任何两点的点及其关联边的色集合不同,所用最小的正整数k被称为G的点可区别边色数,记为x′_(vd)(G).用K_(2n)-E(C_4)表示2n阶完全图删去其中一条4阶路的边后得到的图,文中得到了K_(2n)-E(_4)的点可区别边色数.  相似文献   

10.
In this paper, we study the chaotic numbers of complete bipartite graphs and complete tripartite graphs. For the complete bipartite graphs, we find closed-form formulas of the chaotic numbers and characterize all chaotic mappings. For the complete tripartite graphs, we develop an algorithm running in O(n 4 3) time to find the chaotic numbers, with n 3 the number of vertices in the largest partite set.Research supported by NSC 90-2115-M-036-003.The author thanks the authors of Ref. 6, since his work was motivated by their work. Also, the author thanks the referees for helpful comments which made the paper more readable.  相似文献   

11.
刘慧敏 《数学研究》2007,40(2):223-226
通过比较两个图的色多项式的系数(本文使用了五独立集数)、顶点集、边集、三角形和四圈的个数,证明了K(2,2,6)是色唯一图,从而部分地回答了文[5],[7]中遗留的一个问题,并得到图K(n,n,n 4)(n=2或n 4)是色唯一的.  相似文献   

12.
通过结构分析的方法,考虑各种不同情况,给出了一类联图的点可区别的边染色方法,并得到了它的点可区别的边色数.  相似文献   

13.
通过揭示完全蛛网图和渔网图的结构特点,研究了它们的邻点可区别I-全染色问题,并运用构造法给出了其邻点可区别I-全染色,从而获得了它们的邻点可区别I-全色数.  相似文献   

14.
本文.证明了,当n≥2时,Xat(K_n×K′_n)=2n;当p,q≥2时,Xat(C_(2p)×K_(2q))=2q 3,其中K_n×K′_n是两个不同标号完全图的积图,C_(2p)×K_(2q)是偶圈和偶阶完全图的积图.  相似文献   

15.
16.
The total chromatic number XT(G) of a graph G is the minimum number of colors needed to color the elements (vertices and edges) of G such that no adjacent or incident pair of elements receive the same color. G is called Type 1 if XT(G)=Δ(G) 1. In this paper we prove that the join of a complete bipartite graph Km,n and a cycle Cn is of Type 1.  相似文献   

17.
若干笛卡尔积图的邻点可区别E-全染色   总被引:4,自引:2,他引:2  
图G(V,E)的k是一个正整数,f是V(G)∪E(G)到{1,2,…,k}的一个映射,如果u,v∈V(G),则f(u)≠f(v),f(u)≠f(uv),f(v)≠f(uv),C(u)≠C(v),称f是图G的邻点可区别E-全染色,称最小的数k为图G的邻点可区别E-全色数.得到了Pm×Pn,Pm×Cn,Cm×Cn的邻点可区别E-全色数,其中C(u)={f(u)}∪{f(uv)uv∈E(G)}.  相似文献   

18.
星和完全等二部图联图的点可区别均匀边染色   总被引:1,自引:0,他引:1  
研究了星与完全等二部图的联图Sm∨Kn,n的点可区别均匀边染色。  相似文献   

19.
A decomposition of a complete graph into disjoint copies of a complete bipartite graph is called a ‐design of order n. The existence problem of ‐designs has been completely solved for the graphs for , for , K2, 3 and K3, 3. In this paper, I prove that for all , if there exists a ‐design of order N, then there exists a ‐design of order n for all (mod ) and . Giving necessary direct constructions, I provide an almost complete solution for the existence problem for complete bipartite graphs with fewer than 18 edges, leaving five orders in total unsolved.  相似文献   

20.
简单图G的全染色是指对G的点和边都进行染色.称全染色为正常的如果没有相邻或关联元素染同一种颜色.简单图G=(VE)的正常全染色^称为它的邻点可区别全染色如果对任意两个相邻顶点u、v,有H(u)≠H(v),其中H(u)={(u))U{^(uw)|uw∈E(G))而H(v)={h(u)}U{h(vx)|vx∈E(G)).G...  相似文献   

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