# Computing the partition function for graph homomorphisms

@article{Barvinok2017ComputingTP,
title={Computing the partition function for graph homomorphisms},
author={Alexander I. Barvinok and Pablo Sober{\'o}n},
journal={Combinatorica},
year={2017},
volume={37},
pages={633-650}
}
• Published 6 June 2014
• Mathematics, Computer Science
• Combinatorica
We introduce the partition function of edge-colored graph homomorphisms, of which the usual partition function of graph homomorphisms is a specialization, and present an efficient algorithm to approximate it in a certain domain. Corollaries include effcient algorithms for computing weighted sums approximating the number of k-colorings and the number of independent sets in a graph, as well as an effcient procedure to distinguish pairs of edge-colored graphs with many color-preserving…
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