t-perfection in near-bipartite and in P5-free graphs
نویسندگان
چکیده
A graph is called t-perfect if its stable set polytope is fully described by non-negativity, edge and odd-cycle constraints. We characterise nearbipartite t-perfect and P5-free t-perfect graphs in terms of forbidden tminors. Moreover, we show that P5-free t-perfect graphs can always be coloured with three colours, and that they can be recognised in polynomial time.
منابع مشابه
t-Perfection in P5-Free Graphs
A graph is called t-perfect if its stable set polytope is fully described by non-negativity, edge and odd-cycle constraints. We characterise P5-free t-perfect graphs in terms of forbidden t-minors. Moreover, we show that P5-free t-perfect graphs can always be coloured with three colours, and that they can be recognised in polynomial time.
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تاریخ انتشار 2015