The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A105505 Numbers n such that 5 is the leading digit of the n-th Fibonacci number in decimal representation. 10
 5, 10, 29, 34, 53, 58, 77, 96, 101, 120, 125, 139, 144, 163, 168, 187, 192, 206, 211, 230, 235, 254, 273, 278, 297, 302, 321, 340, 345, 364, 369, 388, 407, 412, 431, 436, 455, 474, 479, 498, 503, 522, 541, 546, 565, 570, 584, 589, 608, 613, 632, 637, 651, 656 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS A008963(a(n)) = 5; A105515(a(n)) = A105515(a(n) - 1) + 1. LINKS Robert Israel, Table of n, a(n) for n = 1..10000 FORMULA a(n) ~ kn by the equidistribution theorem, where k = log(10)/(log(6) - log(5)) = 12.629253.... - Charles R Greathouse IV, Oct 07 2016 EXAMPLE a(10)=120: A008963(120) = A000030(A000045(120)) = A000030(5358359254990966640871840) = 5. MAPLE ld:= x -> floor(x/10^ilog10(x)): select(n -> ld(combinat:-fibonacci(n))=5, [\$1..1000]); # Robert Israel, Oct 26 2020 MATHEMATICA Select[Range[700], First[IntegerDigits[Fibonacci[#]]]==5&] (* Harvey P. Dale, Jul 31 2018 *) PROG (PARI) is(n)=digits(fibonacci(n))[1]==5 \\ Charles R Greathouse IV, Oct 07 2016 CROSSREFS Cf. A000030, A000045, A072703, A105501, A105502, A105503, A105504, A105506, A105507, A105508, A105509. Sequence in context: A105862 A338662 A093029 * A005514 A069921 A053818 Adjacent sequences:  A105502 A105503 A105504 * A105506 A105507 A105508 KEYWORD nonn,base AUTHOR Reinhard Zumkeller, Apr 11 2005 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified May 16 06:54 EDT 2021. Contains 343939 sequences. (Running on oeis4.)