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.

A113176 Product_{p|n} F(p), where F(p) is the p-th Fibonacci number and where the product is over the distinct prime divisors of n.

Original entry on oeis.org

1, 1, 2, 1, 5, 2, 13, 1, 2, 5, 89, 2, 233, 13, 10, 1, 1597, 2, 4181, 5, 26, 89, 28657, 2, 5, 233, 2, 13, 514229, 10, 1346269, 1, 178, 1597, 65, 2, 24157817, 4181, 466, 5, 165580141, 26, 433494437, 89, 10, 28657, 2971215073, 2, 13, 5, 3194, 233
Offset: 1

Views

Author

Leroy Quet, Oct 16 2005

Keywords

Examples

			63 = 3^2 * 7^1. So a(63) = F(3) * F(7) = 2 * 13 = 26.
		

Crossrefs

Programs

  • Mathematica
    b[t_]:=Fibonacci[First[t]] a[n_]:=Apply[Times, Map[b, FactorInteger[n]]] (* Esa Peuha, Oct 26 2005 *)
    Table[Times@@(Fibonacci[#]&/@FactorInteger[n][[All,1]]),{n,60}] (* Harvey P. Dale, May 31 2019 *)
  • Sage
    [1]+[prod([fibonacci(p) for p in prime_factors(n)]) for n in range(2,53)] # Danny Rorabaugh, Apr 03 2015

Formula

Multiplicative with a(p^e) = F(p). - Franklin T. Adams-Watters, Jun 05 2006

Extensions

More terms from Esa Peuha (esa.peuha(AT)helsinki.fi), Oct 26 2005