%I #8 Jun 26 2018 19:15:13
%S 1,3,12,22,25,47,44,69,48,71,66,98,125,160,129,145,101,128,154,151,
%T 212,228,217,210,223,176,226,198,313,218,316,314,378,364,326,350,353,
%U 394,344,387,399,421,376,390,494,431,449,509,510,561,501
%N Smallest k such that 6^k has exactly n 2's in its decimal representation.
%t a = {}; Do[k = 1; While[ Count[ IntegerDigits[6^k], 2] != n, k++ ]; a = Append[a, k], {n, 0, 50} ]; a
%t With[{c=6^Range[600]},Flatten[Table[Position[c,_?(DigitCount[#,10,2]==n&),{1},1],{n,0,50}]]] (* _Harvey P. Dale_, Dec 29 2014 *)
%K base,nonn
%O 0,2
%A _Robert G. Wilson v_, Aug 10 2001
%E Name corrected by _Jon E. Schoenfield_, Jun 26 2018