# Math Help - set ..

1. ## set ..

for the set X, with n elements; get the appropriate solution for:

a) sigma (|A|-1)2 sum over all A (subsets of X).

b) sigma 2|A|3|B| sum over all A,B (subsets of X).

2. ## Re: set ..

For a), you can use formulas (6a) and (6b) on this page.

3. ## Re: set ..

i solved a) today afternoon. : )
thx

dont u have any idea about b) ?