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*Proposition:*
If A and B have size `m` and `n`,
respectively, then the size of the set of functions from `A` to
`B` is `n`^{m}:

forallA,B,minN,ninN:(| A| =m/\ |B| =n) => |A->B| =n^{m}.

If `A` is of size `n`, then `A` has 2^{n} subsets:

forallA,ninN:| A| =n=> |P(A)| = 2^{n}.

Author: Wolfgang Schreiner

Last Modification: December 7, 1999