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%I #4 Oct 02 2013 15:47:16
%S 9,12,67,43,78,144,182,220,206,309,354,287,350,316,420,423,515,551,
%T 591,667,691,595,798,608,824,789,790,1079,839,1030,1022,1050,1195,
%U 1100,1253,1217,1307,1152,1293,1466,1397,1436,1611,1521,1738,1749,1645,1721,1725
%N a(n)-th Fibonacci number is the smallest Fibonacci number containing exactly n 4's.
%e a(2)=12 since 12th Fibonacci number i.e. 144 contains exactly two 4's.
%t With[{fibs=Fibonacci[Range[5000]]},Flatten[Table[Position[fibs,_?(DigitCount[ #,10,4]==n&)][[1]],{n,50}]]] (* _Harvey P. Dale_, Jan 26 2013 *)
%K base,nonn
%O 1,1
%A _Shyam Sunder Gupta_, Jul 14 2002
%E More terms from _Harvey P. Dale_, Jan 26 2013