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.

A364952 Dirichlet inverse of A364557, which is Möbius transform of A005941.

Original entry on oeis.org

1, -1, -2, -1, -4, 2, -8, -1, 0, 4, -16, 2, -32, 8, 12, -1, -64, 0, -128, 4, 24, 16, -256, 2, 8, 32, 0, 8, -512, -12, -1024, -1, 48, 64, 56, 0, -2048, 128, 96, 4, -4096, -24, -8192, 16, -8, 256, -16384, 2, 48, -8, 192, 32, -32768, 0, 112, 8, 384, 512, -65536, -12, -131072, 1024, -16, -1, 224, -48, -262144, 64, 768
Offset: 1

Views

Author

Antti Karttunen, Aug 29 2023

Keywords

Crossrefs

Programs

  • PARI
    A364557(n) = if(1==n, 1, 2^(primepi(vecmax(factor(n)[, 1]))+(bigomega(n)-omega(n))-1));
    memoA364952 = Map();
    A364952(n) = if(1==n,1,my(v); if(mapisdefined(memoA364952,n,&v), v, v = -sumdiv(n,d,if(dA364557(n/d)*A364952(d),0)); mapput(memoA364952,n,v); (v)));

Formula

a(1) = 1, and for n > 1, a(n) = -Sum_{d|n, dA364557(n/d) * a(d).
a(p) = -A000079(A000720(p)-1) for all primes p.