A067460 a(n) = mu(prime(n)-1)+1.

2, 0, 1, 2, 2, 1, 1, 1, 2, 1, 0, 1, 1, 0, 2, 1, 2, 1, 0, 0, 1, 0, 2, 1, 1, 1, 0, 2, 1, 1, 1, 0, 1, 0, 1, 1, 1, 1, 2, 1, 2, 1, 0, 1, 1, 1, 2, 0, 2, 1, 1, 0, 1, 1, 1, 2, 1, 1, 1, 1, 0, 1, 1, 0, 1, 1, 2, 1, 2, 1, 1, 2, 0, 1, 1, 2, 1, 1, 1, 1, 0, 1, 0, 1, 0, 0, 1, 1, 1, 2, 2, 2, 1, 1, 0, 2, 1, 1, 1, 1, 2, 1, 2, 1, 2

Offset: 1

Author

Benoit Cloitre, Feb 23 2002

Keywords

• easy
• nonn

Links

• Amiram Eldar, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A008683, A089451.

Programs

Mathematica

a[n_] := MoebiusMu[Prime[n]-1] + 1; Array[a, 100] (* Amiram Eldar, Apr 23 2025 *)

PARI

a(n) = moebius(prime(n)-1) + 1; \\ Amiram Eldar, Apr 23 2025

Formula

a(n) = A089451(n)+1. - R. J. Mathar, Jul 21 2017