A062984 a(n) = M(C(n)), where M(n) is Mertens's function (A002321) and C(n) is Chowla's function (A048050).

0, 0, 0, 0, 0, -2, 0, -1, -1, -2, 0, -1, 0, -2, -2, -2, 0, -3, 0, -2, -1, -3, 0, -1, -2, -1, -2, -1, 0, -1, 0, -3, -2, -3, -2, -3, 0, -2, -1, -3, 0, -3, 0, 0, -4, -2, 0, -3, -2, -2, -3, -3, 0, 0, -1, -1, -1, -4, 0, -3, 0, -3, 0, -1, -2, -2, 0, -1, -1, -4, 0, -2, 0, 0, -3, -1, -2, -2, 0, -3, 0, -3, 0, -4, -1, -3, -4, -1, 0, -1, -3, -3, -2, -3

Offset: 1

Author

Jason Earls, Jul 25 2001

Keywords

• easy
• sign

Links

• Harry J. Smith, Table of n, a(n) for n = 1..2000

Crossrefs

Cf. A002321, A048050.

Programs

Mathematica

A062984[n_] := Sum[MoebiusMu[k], {k, DivisorSigma[1, n] - n - 1}];
Array[A062984, 100] (* Paolo Xausa, May 03 2024 *)

PARI

M(n)=sum(k=1,n,moebius(k));
C(n)=sigma(n)-n-1;
j=[]; for(n=1,350,j=concat(j,M(C(n)))); j

PARI

{ for (n=1, 2000, a=sum(k=1, sigma(n) - n - 1, moebius(k)); write("b062984.txt", n, " ", a) ) } \\ Harry J. Smith, Aug 15 2009