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.

A345045 a(n) = A047994(n) / A345044(n), where A047994(n) is multiplicative with a(p^e) = p^e - 1, and A345044(n) gives the least common multiple of the same factors.

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 3, 1, 2, 1, 1, 2, 1, 2, 1, 1, 1, 2, 1, 1, 2, 1, 1, 4, 1, 1, 1, 1, 1, 2, 3, 1, 1, 2, 1, 2, 1, 1, 2, 1, 1, 2, 1, 4, 2, 1, 1, 2, 2, 1, 1, 1, 1, 2, 3, 2, 2, 1, 1, 1, 1, 1, 6, 4, 1, 2, 1, 1, 4, 6, 1, 2, 1, 2, 1, 1, 1, 2, 3, 1, 2, 1, 1, 4
Offset: 1

Views

Author

Antti Karttunen, Jun 07 2021

Keywords

Crossrefs

Programs

  • PARI
    A345045(n) = { my(f=factor(n)~, g=vector(#f, i, (f[1, i]^f[2, i])-1)); factorback(g)/lcm(g); };

Formula

a(n) = A047994(n) / A345044(n).