Collapse closed classes of graphs and graph parameters
نویسنده
چکیده
We characterize classes of multi-graphs that by a transformation of Schrijver give so called invariant ring in tensor algebra. This property enables us subsequently to show, that whenever we have an edge reflection positive and multiplicative graph parameter defined on this class such that its value on vertexless loop is a natural number, it can be represented in edge coloring model.
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تاریخ انتشار 2009