%I #15 Nov 02 2014 01:20:28
%S 0,1,27,343,64,125,64,27,8,729,1000,91125,125,1331,140608,15625,216,
%T 1728,85184,2197,205379,216,226981,103823,13824,125,9261,27,1728,729,
%U 39304,1331,5832,1331,343,35937,97336,3375,13824,39304,4096,531441,42875,343
%N The smallest cube containing n as a substring.
%H T. D. Noe, <a href="/A178983/b178983.txt">Table of n, a(n) for n = 0..1000</a>
%e a(3) = 7^3 = 343, because it contains 3 as a substring and no smaller cube contains 3.
%t subs[n_] := Module[{d = IntegerDigits[n], len}, len = Length[d]; Union[Flatten[Table[FromDigits[Take[d, {i, k}]], {k, len}, {i, k}]]]]; Table[k = 0; While[! MemberQ[subs[k^3], n], k++]; k^3, {n, 0, 100}] (* _T. D. Noe_, Nov 06 2013 *)
%o (Ruby)
%o # For a given nonnegative integer n,
%o # find the smallest nonnegative cube that contains it as a substring.
%o NUM_TERMS = 30
%o (0...NUM_TERMS).each{ |i|
%o (0..(1.0/0.0)).each{ |j|
%o (print "#{j*j*j}" + ", "; break) if "#{j*j*j}".include?("#{i}")
%o }
%o }
%Y Cf. A029943, A029947.
%K nonn,easy,base
%O 0,3
%A _Andy Martin_, Jan 02 2011
%E Edited by _Alois P. Heinz_, Jan 02 2011
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