Graphs Admitting k-NU Operations. Part 1: The Reflexive Case
نویسندگان
چکیده
We describe a generating set for the variety of reflexive graphs that admit a compatible k-ary near-unanimity operation; we further delin-eate a very simple subset that generates the variety of j-absolute retracts; in particular we show that the class of reflexive graphs with a 4-NU operation coincides with the class of 3-absolute retracts. Our results generalise and encompass several results on NU-graphs and absolute retracts.
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ورودعنوان ژورنال:
- SIAM J. Discrete Math.
دوره 27 شماره
صفحات -
تاریخ انتشار 2013