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#1 2012-12-10 07:59:20

jacks
Member
Registered: 2012-11-21
Posts: 80

sum of subsets

Consider all

non empty subsets  of the set
.

For every subset we find the product of each of these elements.

Sum of all these products is?

Last edited by jacks (2012-12-10 07:59:38)

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#2 2012-12-10 08:46:45

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 86,705

Re: sum of subsets

Hi;

I am getting (n+1)! - 1 but I do not know of a proof of that.


In mathematics, you don't understand things. You just get used to them.
Of course that result can be rigorously obtained, but who cares?
Combinatorics is Algebra and Algebra is Combinatorics.

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#3 2012-12-10 13:20:05

scientia
Member
Registered: 2009-11-13
Posts: 222

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