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.

A113175 Replace each prime p in prime-factorization of n with p-th Fibonacci number.

Original entry on oeis.org

1, 1, 2, 1, 5, 2, 13, 1, 4, 5, 89, 2, 233, 13, 10, 1, 1597, 4, 4181, 5, 26, 89, 28657, 2, 25, 233, 8, 13, 514229, 10, 1346269, 1, 178, 1597, 65, 4, 24157817, 4181, 466, 5, 165580141, 26, 433494437, 89, 20, 28657, 2971215073, 2, 169, 25, 3194, 233
Offset: 1

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Author

Leroy Quet, Oct 16 2005

Keywords

Comments

If, for p = prime, p^(m_{n,p}) is highest power of p dividing n, m = nonnegative integer, then a(n) is product over all primes of F(p)^(m_{n,p}), where F(p) = p-th Fibonacci number (A000045).

Examples

			63 = 3^2 * 7^1. So a(63) = F(3)^2 * F(7)^1 = 4 * 13 = 52.
		

Crossrefs

Programs

  • Maple
    a:= n-> mul(combinat[fibonacci](i[1])^i[2], i=ifactors(n)[2]):
    seq(a(n), n=1..52);  # Alois P. Heinz, Jan 14 2025
  • Mathematica
    Times@@@Table[Fibonacci[#[[1]]]^#[[2]]&/@FactorInteger[n],{n,60}] (* Harvey P. Dale, Mar 30 2024 *)
  • Sage
    [1]+[prod([fibonacci(x[0])^x[1] for x in factor(n)]) for n in range(2,53)] # Danny Rorabaugh, Apr 03 2015

Formula

Totally multiplicative with a(p) = F(p). - Franklin T. Adams-Watters, Jun 05 2006

Extensions

More terms from Esa Peuha (esa.peuha(AT)helsinki.fi), Oct 26 2005
Previous Mathematica program deleted by Harvey P. Dale, Mar 30 2024