cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A177231 Fibonacci numbers whose decimal expansion does not contain any digit "2".

Original entry on oeis.org

0, 1, 3, 5, 8, 13, 34, 55, 89, 144, 377, 610, 987, 1597, 4181, 6765, 10946, 17711, 46368, 196418, 317811, 39088169, 165580141, 433494437, 701408733, 1134903170, 1836311903, 17167680177565, 117669030460994, 806515533049393, 99194853094755497, 160500643816367088
Offset: 1

Views

Author

Carmine Suriano, May 05 2010

Keywords

Comments

The probability that Fibonacci(n) contains no 2's goes to zero as n grows to infinity. The maximum term is possibly Fibonacci(101) having 21 digits, none of them being "2".

Examples

			a(5) = 8 is the 5th Fibonacci number having no digit 2's.
		

Crossrefs

Programs

  • Magma
    [0] cat [Fibonacci(n): n in [2..150] | not 2 in Intseq(Fibonacci(n))]; // Vincenzo Librandi, May 09 2019
  • Maple
    F:= combinat[fibonacci]:
    q:= n-> not(2 in convert(n, base, 10)):
    select(q, {F(n)$n=0..101})[];  # Alois P. Heinz, May 06 2019
  • Mathematica
    Join[{0}, Select[Fibonacci[Range[2, 50]], DigitCount[#, 10, 2]==0&]] (* Harvey P. Dale, Oct 01 2017 *)

Extensions

Edited by Charles R Greathouse IV, Aug 03 2010
a(1) changed from 1 to 0 by Alois P. Heinz, May 06 2019