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7
Double Summation
Double Summation
Source:
March 2, 2008
floor function
ratio
function
quadratics
calculus
integration
geometric series
Problem Statement
Compute \sum_{n \equal{} 1}^\infty\sum_{k \equal{} 1}^{n \minus{} 1}\frac {k}{2^{n \plus{} k}}.
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