A073557 Number of Fibonacci numbers F(k), k <= 10^n, whose initial digit is 1.
3, 30, 301, 3011, 30103, 301031, 3010300, 30103001, 301029995, 3010299957, 30102999568
Offset: 1
Examples
a(2) = 30 because there are 30 Fibonacci numbers up to 10^2 whose initial digit is 1.
Programs
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PARI
default(realprecision, 10^4); m=log((1+sqrt(5))/2); lista(nn) = {my(d=log(10)/m, r=log(sqrt(5))/m, s=log(5-sqrt(5))/m, t=0, u=1); for(n=1, nn, u=10*u; while(sJinyuan Wang, Feb 21 2020
Formula
Limit_{n->infinity} a(n)/10^n = log(2), where the base is 10. - Robert Gerbicz, Sep 05 2002
Extensions
More terms from Robert Gerbicz, Sep 05 2002
a(9)-a(10) from Jinyuan Wang, Feb 21 2020
a(11) from Sean A. Irvine, Dec 04 2024