Clone

of an operation

Any set of finitary operations of the form that is closed with respect to composition and contains all the projections , defined by

for any -tuple in , where , and is an arbitrary fixed set. By a composition of operations and one means the operation defined by the formula

for some , where the sets of variables , and satisfy the equality

Comments

The name "clone" was invented by P. Hall. It first appeared in print in (the first edition of) [a1].

References

[a1]	P.M. Cohn, "Universal algebra" , Reidel (1981)