A181587 If n is even, a(n) = 0, if n is odd, a(n) = A002321(n), where A002321 is Mertens's function.

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

Offset: 1

Author

Mats Granvik, Oct 31 2010

Keywords

• sign
• look

Links

• Antti Karttunen, Table of n, a(n) for n = 1..65537

Crossrefs

Cf. A000035, A002321.

Programs

PARI

A181587(n) = if(n%2, sum(k=1, n, moebius(k)), 0); \\ Antti Karttunen, Sep 30 2018

Formula

a(n) = A000035(n)*A002321(n).

Extensions

Definition corrected and more terms by Antti Karttunen, Sep 30 2018

Incorrect g.f. removed by Georg Fischer, Nov 09 2022