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MiS Preprint
28/2011
Relations Between Graphs
Yangjing Long, Ling Yang, Peter F. Stadler and Jürgen Jost
Abstract
Given two graphs G=(V_G,E_G) and H=(V_H,E_H), we ask under which conditions there is a relation that generates the edges of H given the structure of G. This construction generalizes full homomorphisms of graphs and naturally leads to generalized notions of retractions, cores, and co-cores of graphs.