The complexity of counting surjective homomorphisms and compactions
A homomorphism from a graph $G$ to a graph $H$ is a function from the vertices of $G$ to the vertices of $H$ that preserves edges. A homomorphism is surjective if it uses all of the vertices of $H$, and it is a compaction if it uses all of the vertices of $H$ and all of the nonloop edges of $H$. Hel...
| Main Authors: | , , |
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| Formato: | Journal article |
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Society for Industrial and Applied Mathematics
2019
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