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A050621
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Smallest n-digit number divisible by 2^n.
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27
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2, 12, 104, 1008, 10016, 100032, 1000064, 10000128, 100000256, 1000000512, 10000001024, 100000002048, 1000000004096, 10000000008192, 100000000016384, 1000000000032768, 10000000000065536, 100000000000131072
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OFFSET
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1,1
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COMMENTS
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Quotients arising from this sequence give A034478 ((5^(n-1)+1)/2).
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LINKS
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FORMULA
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a(n) = 10^(n-1) + 2^(n-1).
G.f.: Q(0) where Q(k)= 1 + 5^k/(1 - 2*x/(2*x + 5^k/Q(k+1) )); (continued fraction ). - Sergei N. Gladkovskii, Apr 10 2013
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MATHEMATICA
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CoefficientList[Series[2 (1 - 6 x)/((1 - 2 x) (1 - 10 x)), {x, 0, 30}], x] (* Vincenzo Librandi, Sep 12 2014 *)
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PROG
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CROSSREFS
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KEYWORD
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nonn,base,easy
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AUTHOR
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STATUS
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approved
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