A Strongly Rigid Ternary Relation
A binary relation ρ on a set U is strongly rigid if every universal algebra on U such that ρ is a subuniverse of its square is trivial. Rosenberg (1973) found a strongly rigid binary relation on every universe U of at least 3 elements. Fearnley (1994) exhibited another strongly binary rigid relation. In this article we present a strongly rigid ternary relation on a finite domain, and we propose a possible strongly rigid k-ary relation.
Keywords: Clones, propositional logic
2010 Mathematics Subject Classification. Primary: 08A40; Secondary: 03B05