A073562 - OEIS

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A073562

Number of Fibonacci numbers F(k), k <= 10^n, whose initial digit is 6.

0, 6, 67, 668, 6695, 66947, 669467, 6694672, 66946785, 669467892, 6694678954

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

LINKS

Table of n, a(n) for n=1..11.

FORMULA

Limit_{n->oo} a(n)/10^n = log(7/6), where the base is 10. - Robert Gerbicz, Sep 05 2002

EXAMPLE

a(2) = 6 because there are 6 Fibonacci numbers up to 10^2 whose initial digit is 6.

PROG

(PARI) lista(nn) = my(m=log(quadgen(5)), c=0, d=log(10)/m, q, r=log(sqrt(5))/m, s=4-log(6)/m, t=5-log(7)/m, u=1); for(n=1, nn, u=10*u; until(u<r+=d, q=frac(r); if(q<s || q>t, c++)); print1(c - (q<s&&r-d+3>u || q>t&&r-d+4>u), ", ")); \\ Jinyuan Wang, Dec 09 2024

CROSSREFS

Sequence in context: A024203 A355051 A231598 * A354320 A230342 A239301

Adjacent sequences: A073559 A073560 A073561 * A073563 A073564 A073565

KEYWORD

nonn,base,more,changed

AUTHOR

Shyam Sunder Gupta, Aug 15 2002

EXTENSIONS

More terms from Robert Gerbicz, Sep 05 2002

a(9)-a(11) from Sean A. Irvine and Jinyuan Wang, Dec 10 2024

STATUS

approved