1,5

Florian Lang, Table of n, a(n) for n = 1..9998

(PARI) seq(n)={dirdiv(vector(n, n, n==1), vector(n, n, sum(k=1, n, moebius(k))))} \\ Andrew Howroyd, Apr 07 2020

Cf. A002321.

Sequence in context: A086421 A290399 A109400 * A202389 A210868 A176853

Adjacent sequences: A333828 A333829 A333830 * A333832 A333833 A333834

sign,easy

Florian Lang, Apr 07 2020

approved