منابع مشابه
Dual graph homomorphism functions
For any two graphs F and G, let hom(F,G) denote the number of homomorphisms F → G, that is, adjacency preserving maps V (F ) → V (G) (graphs may have loops but no multiple edges). We characterize Institute of Mathematics, Eötvös Loránd University, Budapest, Hungary. Email: [email protected]. Research sponsored by OTKA Grant No. 67867. CWI and University of Amsterdam, Amsterdam, The Netherlands....
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ژورنال
عنوان ژورنال: Discrete Mathematics
سال: 1990
ISSN: 0012-365X
DOI: 10.1016/0012-365x(90)90270-r