Characterizations of Strongly Regular Graphs: Part II: Bose-Mesner algebras of graphs
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On Spin Models, Triply Regular Association Schemes, and Duality
Motivated by the construction of invariants of links in 3-space, we study spin models on graphs for which all edge weights (considered as matrices) belong to the Bose-Mesner algebra of some association scheme. We show that for series-parallel graphs the computation of the partition function can be performed by using seriesparallel reductions of the graph appropriately coupled with operations in...
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