THE COORDINATE REPRESENTATION OF A GRAPH AND N-UNIVERSAL GRAPH OF RADIUS-1

Authors
Citation
Av. Ivashchenko, THE COORDINATE REPRESENTATION OF A GRAPH AND N-UNIVERSAL GRAPH OF RADIUS-1, Discrete mathematics, 120(1-3), 1993, pp. 107-114
Citations number
10
Categorie Soggetti
Mathematics, Pure",Mathematics
Journal title
ISSN journal
0012365X
Volume
120
Issue
1-3
Year of publication
1993
Pages
107 - 114
Database
ISI
SICI code
0012-365X(1993)120:1-3<107:TCROAG>2.0.ZU;2-R
Abstract
Every graph can be represented as the intersection graph on a family o f closed unit cubes in Euclidean space E(n). Cube vertices have intege r coordinates. The coordinate matrix, A(G)={v(nk)} of a graph G is def ined by the set of cube coordinates. The imbedded dimension of a graph , Bp(G), is a number of columns in matrix A(G) such that each of them has at least two distinct elements v(nk) not-equal v(pk). We show that Bp(G)=cub(G) for some graphs, and Bp(G) less-than-or-equal-to n-2 for any graph G on n vertices. The coordinate matrix uses to obtain the g raph U of radius 1 with 3n-2 vertices that contains as an induced subg raph a copy of any graph on n vertices.