Dichotomy Theorems for Homomorphism Polynomials of Graph Classes
نویسندگان
چکیده
منابع مشابه
Dichotomy Theorems for Homomorphism Polynomials of Graph Classes
In this paper, we will show dichotomy theorems for the computation of polynomials corresponding to evaluation of graph homomorphisms in Valiant’s model. We are given a fixed graph H and want to find all graphs, from some graph class, homomorphic to this H. These graphs will be encoded by a family of polynomials. We give dichotomies for the polynomials for cycles, cliques, trees, outerplanar gra...
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For digraphs D and H , a mapping f : V (D)→V (H) is a homomorphism of D to H if uv ∈ A(D) implies f (u) f (v) ∈ A(H). If, moreover, each vertex u ∈ V (D) is associated with costs ci (u), i ∈ V (H), then the cost of the homomorphism f is ∑ u∈V (D) c f (u)(u). For each fixed digraph H , we have the minimum cost homomorphism problem for H (abbreviated MinHOM(H )). The problem is to decide, for an ...
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ژورنال
عنوان ژورنال: Journal of Graph Algorithms and Applications
سال: 2016
ISSN: 1526-1719
DOI: 10.7155/jgaa.00382