0 M ay 2 00 5 Contractors and connectors of graph algebras ∗ László
نویسندگان
چکیده
We study generalizations of the " contraction-deletion " relation of the Tutte polynomial, and other similar simple operations, to other graph parameters. The question can be set in the framework of graph algebras introduced by Freedman, Lovász and Schrijver in [2], and it relates to their behavior under basic graph operations like contraction and subdivision. Graph algebras were introduced in [2] to study and characterize homomorphism functions. We prove that for homomorphism functions, these graph algebras have special elements called " contractors " and " connectors ". This gives a new characterization of homomorphism functions.
منابع مشابه
Contractors and connectors of graph algebras
We study generalizations of the “contraction-deletion” relation of the Tutte polynomial, and other similar simple operations, to other graph parameters. The question can be set in the framework of graph algebras introduced by Freedman, Lovász and Schrijver in [2], and it relates to their behavior under basic graph operations like contraction and subdivision. Graph algebras were introduced in [2...
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