On Maltsev Digraphs

[摘要] We study digraphs preserved by a Maltsev operation: Maltsev digraphs. We show that these digraphs retract either onto a directed path or to the disjoint union of directed cycles, showing in this way that the constraint satisfaction problem for Maltsev dig

[学科分类] 离散数学和组合数学

[关键词] digraph;polymorphism;constraint satisfaction problem