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%I #15 Jun 26 2018 04:56:37
%S 1,8,17,23,58,59,40,57,74,92,93,114,112,143,155,156,160,193,113,195,
%T 212,214,215,236,216,287,291,295,309,289,288,360,274,371,427,418,444,
%U 462,478,464,466,494,530,545,482,561,481,597,644,689,650
%N Smallest k such that 5^k has exactly n 9's in its decimal representation.
%H Harry J. Smith, <a href="/A063594/b063594.txt">Table of n, a(n) for n = 0..150</a>
%t a = {}; Do[k = 1; While[ Count[ IntegerDigits[5^k], 9] != n, k++ ]; a = Append[a, k], {n, 0, 50} ]; a
%o (PARI) a(n)={my(k=1); while(n<>#select(d->d==9, digits(5^k)), k++); k} \\ _Harry J. Smith_, Aug 26 2009, _Andrew Howroyd_, Jun 26 2018
%K base,nonn
%O 0,2
%A _Robert G. Wilson v_, Aug 10 2001
%E Name corrected by _Jon E. Schoenfield_, Jun 25 2018
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