A note on an extension of facet - de ning digraphs
نویسنده
چکیده
In this paper we present suucient conditions for unweighted digraphs to induce facet-deening inequalities of the linear ordering polytope P n. We introduce constructive operations (Identiication (of nodes),5-Extension) for generating new facets of P n by using already known facets. The identiication generates new digraphs by identiication two nodes of the source di-graph and presented for arbitrary unweighted digraphs. On examples of MM obius ladders we show a possible way to nd two nodes, which can be identiied to obtain new facet-deening digraph. By connecting MM obius ladders with special digraphs 5-Extension generates new facet-deening digraphs to which we can apply 5-Extension repeatedly.
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