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.

A369010 Exponential of Mangoldt function M(n) applied to primorial base exp-function: a(n) = A014963(A276086(n)).

Original entry on oeis.org

1, 2, 3, 1, 3, 1, 5, 1, 1, 1, 1, 1, 5, 1, 1, 1, 1, 1, 5, 1, 1, 1, 1, 1, 5, 1, 1, 1, 1, 1, 7, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 7, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 7, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1
Offset: 0

Views

Author

Antti Karttunen, Jan 14 2024

Keywords

Comments

Also LCM-transform of A276086, because A276086 has the S-property explained in the comments of A368900.

Crossrefs

Cf. A014963, A060735 (positions of terms > 1), A276086, A368900.

Programs

  • PARI
    A014963(n) = { ispower(n, , &n); if(isprime(n), n, 1); };
    A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); };
    A369010(n) = A014963(A276086(n));
    
  • PARI
    up_to = 510511; \\ = 1+A002110(7);
    LCMtransform(v) = { my(len = length(v), b = vector(len), g = vector(len)); b[1] = g[1] = 1; for(n=2,len, g[n] = lcm(g[n-1],v[n]); b[n] = g[n]/g[n-1]); (b); };
    v369010 = LCMtransform(vector(up_to,n,A276086(n-1)));
    A369010(n) = v369010[1+n];

Formula

a(n) = A014963(A276086(n)).
For n > 0, a(n) = lcm {1..A276086(n)} / lcm {1..A276086(n-1)}.