Retracts and Q-independence
نویسنده
چکیده
A non-empty set X of a carrier A of an algebra A is called Q-independent if the equality of two term functions f and g of the algebra A on any finite system of elements a1, a2, . . . , an of X implies f(p(a1), p(a2), . . . , p(an)) = g(p(a1), p(a2), . . . , p(an)) for any mapping p ∈ Q. An algebra B is a retract of A if B is the image of a retraction (i.e. of an idempotent endomorphism of B). We investigate Q-independent subsets of algebras which have a retraction in their set of term functions.
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