Some Notes on Nuf Digraphs
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چکیده
For the moment, we outline how to characterise undirected, irreflexive graphs that admit a near-unanimity operation of arity at most k using the notion of dual of a tree; the same is done for reflexive graphs, and for directed bipartite graphs. We hope to complete this by showing that the generating sets for the varieties in question contain only chordal extensible graphs.
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تاریخ انتشار 2006