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Symmetric Operations on Equivalence Relations
Matteo Mainetti
Sirindhorn International Institute of Technology, Thammasat University, Patumthani 12121 Thailand
Annals of Combinatorics 7 (3) p.325-348 September, 2003
AMS Subject Classification: 05A18, 05C90, 03E02, 91D30
A new binary operation on the family of equivalence relations was introduced and studied by Britz, Mainetti, and Pezzoli. In this paper we give an equivalent, easier to grasp, definition of the same binary operation, and we prove it to be just an example of a bigger family of binary operations, which are shown to have interesting interpretation and meaning.
Keywords: equivalence relation, Jónsson type, trust graph


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