A054585 Sum_{d=1..n} phi(d)*mu(d).

0, 1, 0, -2, -2, -6, -4, -10, -10, -10, -6, -16, -16, -28, -22, -14, -14, -30, -30, -48, -48, -36, -26, -48, -48, -48, -36, -36, -36, -64, -72, -102, -102, -82, -66, -42, -42, -78, -60, -36, -36, -76, -88, -130, -130, -130, -108, -154, -154, -154, -154, -122, -122, -174, -174, -134, -134, -98, -70, -128

Offset: 0

Author

N. J. A. Sloane, Apr 12 2000

Keywords

• sign

Links

• Charles R Greathouse IV, Table of n, a(n) for n = 0..10000

Crossrefs

Partial sums of A097945.

Programs

PARI

a(n)=my(s); forsquarefree(k=1, n, s += moebius(k)*eulerphi(k)); s \\ Charles R Greathouse IV, Jan 07 2018

PARI

first(n)=my(v=vector(n),s); forsquarefree(k=1, n, v[k[1]] = s+=moebius(k)*eulerphi(k)); for(k=4,n, if(v[k]==0, v[k]=v[k-1])); concat(0, v) \\ Charles R Greathouse IV, Jan 07 2018