A Rewriting Approach to Graph Invariants

نویسنده

  • Lars Hellström
چکیده

The Generic Diamond Lemma of the author is applied to the problem of classifying all graph invariants satisfying a contract–delete recursion (like that of the chromatic polynomial). As expected, the recursion for the Tutte polynomial is found, along with some more degenerate invariants. The purpose of this exercise is to demonstrate techniques for applying the diamond lemma to diagrammatic calculations in general. In addition, a concept of ‘semigraph’ is defined and some related elementary constructions of interest for algebraic applications are given.

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تاریخ انتشار 2007