منابع مشابه
Graph Homomorphisms, Circular Colouring, and Fractional Covering by H-cuts
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For graphs G and H , a homomorphism from G to H is a function φ : V (G) → V (H), which maps vertices adjacent in G to adjacent vertices of H . A homomorphism is locally injective if no two vertices with a common neighbor are mapped to a single vertex in H . Many cases of graph homomorphism and locally injective graph homomorphism are NPcomplete, so there is little hope to design polynomial-time...
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ژورنال
عنوان ژورنال: Bulletin of the Australian Mathematical Society
سال: 1999
ISSN: 0004-9727,1755-1633
DOI: 10.1017/s0004972700032627