MathDB

3

Part of 2007 Federal Competition For Advanced Students, Part 1

Problems(1)

38th Austrian Mathematical Competition 2007

Source: round2 problem3 - product of the elements of subsets

2/7/2009
Let M(n )\equal{}\{\minus{}1,\minus{}2,\ldots,\minus{}n\}. For every non-empty subset of M(n) M(n ) we consider the product of its elements. How big is the sum over all these products?
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