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National Olympiad First Round
2012 National Olympiad First Round
34
34
Part of
2012 National Olympiad First Round
Problems
(1)
Turkish NMO First Round - 2012 Problem - 34 {Number Theory}
Source:
7/1/2012
If
10
10
10
divides the number
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1\cdot2^1+2\cdot2^2+3\cdot2^3+\dots+n\cdot2^n
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, what is the least integer
n
≥
2012
n\geq 2012
n
≥
2012
?
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<span class='latex-bold'>(A)</span>\ 2012 \qquad <span class='latex-bold'>(B)</span>\ 2013 \qquad <span class='latex-bold'>(C)</span>\ 2014 \qquad <span class='latex-bold'>(D)</span>\ 2015 \qquad <span class='latex-bold'>(E)</span>\ 2016
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