## Abstract HedrlΓn and Pultr proved that for any monoid **M** there exists a graph __G__ with endomorphism monoid isomorphic to **M**. In this paper we give a construction __G__(__M__) for a graph with prescribed endomorphism monoid **M**. Using this construction we derive bounds on the minimum nu
On graphs containing a given graph as center
β Scribed by Fred Buckley; Zevi Miller; Peter J. Slater
- Publisher
- John Wiley and Sons
- Year
- 1981
- Tongue
- English
- Weight
- 367 KB
- Volume
- 5
- Category
- Article
- ISSN
- 0364-9024
No coin nor oath required. For personal study only.
β¦ Synopsis
Abstract
We examine the problem of embedding a graph H as the center of a supergraph G, and we consider what properties one can restrict G to have. Letting A(H) denote the smallest difference β£V(G)β£ β β£V(H)β£ over graphs G having center isomorphic to H it is demonstrated that A(H) β€ 4 for all H, and for 0 β€ i β€ 4 we characterize the class of trees T with A(T) = i. for n β₯ 2 and any graph H, we demonstrate a graph G with point and edge connectivity equal to n, with chromatic number X(G) = n + X(H), and whose center is isomorphic to H. Finally, if β£V(H)β£ β₯ 9 and k β₯ β£V(H)β£ + 1, then for n sufficiently large (with n even when k is odd) we can construct a kβregular graph on n vertices whose center is isomorphic to H.
π SIMILAR VOLUMES
## Abstract For a nonempty graph, G, we define p(G) and r(G) to be respectively the minimum order and minimum degree of regularity among all connected regular graphs __H__ having a nontrivial decomposition into subgraphs isomorphic to G. By f(G), we denote the least integer t for which there is a c
## Abstract We consider finite, undirected, and simple graphs __G__ of order __n__(__G__) and minimum degree Ξ΄(__G__). The connectivity ΞΊ(__G__) for a connected graph __G__ is defined as the minimum cardinality over all vertexβcuts. If ΞΊ(__G__)β<βΞ΄(__G__), then Topp and Volkmann 7 showed in 1993 f
## Abstract For a vertex __v__ of a graph __G__, we denote by __d__(__v__) the __degree__ of __v__. The __local connectivity__ ΞΊ(__u, v__) of two vertices __u__ and __v__ in a graph __G__ is the maximum number of internally disjoint __u__ β__v__ paths in __G__, and the __connectivity__ of __G__ is
The hamiltonian path graph H(F) of a graph F is that graph having the same vertex set as F and in which two vertices u and u are adjacent if and only if F contains a hamiltonian u -u path. First, in response to a conjecture of Chartrand, Kapoor and Nordhaus, a characterization of nonhamiltonian grap