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%I #4 Mar 30 2012 17:36:52
%S 1,4,3,5,2,3,4,5,10,1,9,8,15,7,13,6,17,11,21,5,14,9,13,25,4,15,11,7,
%T 17,10,16,25,3,23,14,11,8,13,23,5,12,7,16,9,11,13,17,25,51,2,27,17,13,
%U 11,9,16,7,12,22,5,13,8,11,14,20,3,28,16,13,10,7,11,15,27,4,13,9,14,24,5,11
%N Smallest integer q for which there exists a fraction p/q containing n in its decimal expansion.
%C Inspired by problem 14 on the 2003 American Invitational Mathematics Examination, which asked for a(251). There are some slightly different versions of this sequence. For example, you could consider 1/2 = .5 or 1/2 = .50000...; I chose the latter interpretation here.
%H American Mathematics Competitions, <a href="http://www.unl.edu/amc/">Problem 14</a>
%e a(6) = 3 because 2/3 = .6...; a(42) = 7 because 1/7 = .142...
%Y A081664 gives the numerators.
%K base,frac,nonn
%O 1,2
%A _Joshua Zucker_, Mar 26 2003