OFFSET
1,1
EXAMPLE
a(2)=12 since 12th Fibonacci number i.e. 144 contains exactly two 4's.
MATHEMATICA
With[{fibs=Fibonacci[Range[5000]]}, Flatten[Table[Position[fibs, _?(DigitCount[ #, 10, 4]==n&)][[1]], {n, 50}]]] (* Harvey P. Dale, Jan 26 2013 *)
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Shyam Sunder Gupta, Jul 14 2002
EXTENSIONS
More terms from Harvey P. Dale, Jan 26 2013
STATUS
approved