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%I #5 Jun 26 2018 19:22:31
%S 1,5,12,20,59,58,86,63,72,139,125,159,136,211,204,170,196,197,271,302,
%T 218,308,344,392,309,351,434,488,490,414,529,452,484,523,538,526,594,
%U 522,605,592,705,670,649,672,771,785,691,819,788,887,808
%N Smallest k such that 3^k has exactly n 4's in its decimal representation.
%t a = {}; Do[k = 1; While[ Count[ IntegerDigits[3^k], 4] != n, k++ ]; a = Append[a, k], {n, 0, 50} ]; a
%K base,nonn
%O 0,2
%A _Robert G. Wilson v_, Aug 10 2001
%E Name corrected by _Jon E. Schoenfield_, Jun 26 2018