OFFSET
1,1
LINKS
T. D. Noe, Table of n, a(n) for n = 1..1000
EXAMPLE
a(2)=38 since 38th Fibonacci number i.e. 39088169 contains exactly two 9's.
MATHEMATICA
nn = 50; t = Table[0, {nn}]; cnt = 0; n = 0; While[cnt < nn, n++; f = IntegerDigits[Fibonacci[n]]; c = Count[f, 9]; If[c <= nn && t[[c]] == 0, t[[c]] = n; cnt++]]; t (* T. D. Noe, Dec 04 2013 *)
With[{fs=Table[{n, Count[IntegerDigits[Fibonacci[n]], 9]}, {n, 1800}]}, Table[ SelectFirst[fs, #[[2]]==k&], {k, 50}]][[All, 1]] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Oct 03 2018 *)
PROG
(PARI) okdigs(v, n, d) = {my(digs = digits(v)); sum(i=1, #digs, digs[i] == d) == n; }
a(n, d=9) = {my(i = 0); while (! okdigs(fibonacci(i), n, d), i++); i; } \\ Michel Marcus, Nov 29 2013
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Shyam Sunder Gupta, Jul 14 2002
EXTENSIONS
More terms from Michel Marcus, Nov 29 2013
STATUS
approved