Syntactically Characterizing Local-to-Global Consistency in ORD-Horn
نویسنده
چکیده
Oligopotent Quasi Near-Unanimity Polymorphisms A k -ary function f : Qk → Q where k ≥ 3 is called a quasi near-unanimity function (QNUF) if and only if it satisfies ∀x∀y . f (y , x, x, . . . , x) = f (x, y , x, . . . , x) = · · · · · · = f (x, x, x, . . . , y) = f (x, . . . , x). We say that a polymorphism f of Γ is oligopotent if g(x) = f (x, . . . , x) preserves all relations first-order definable in Γ.
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