Polynomial graph invariants from homomorphism numbers
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چکیده
منابع مشابه
Polynomial graph invariants from homomorphism numbers
The number of homomorphisms hom(G,Kk) from a graph G to the complete graph Kk is the value of the chromatic polynomial of G at a positive integer k. This motivates the following (cf. [3]): Definition 1 A sequence of graphs (Hk), k = (k1, . . . , kh) ∈ N , is strongly polynomial if for every graph G there is a polynomial p(G; x1, . . . , xh) such that hom(G,Hk) = p(G; k1, . . . , kh) for every k...
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ژورنال
عنوان ژورنال: Discrete Mathematics
سال: 2016
ISSN: 0012-365X
DOI: 10.1016/j.disc.2015.11.022