A082909 a(n) = Sum_{d|n} (d mod 3).

1, 3, 1, 4, 3, 3, 2, 6, 1, 6, 3, 4, 2, 6, 3, 7, 3, 3, 2, 9, 2, 6, 3, 6, 4, 6, 1, 8, 3, 6, 2, 9, 3, 6, 6, 4, 2, 6, 2, 12, 3, 6, 2, 9, 3, 6, 3, 7, 3, 9, 3, 8, 3, 3, 6, 12, 2, 6, 3, 9, 2, 6, 2, 10, 6, 6, 2, 9, 3, 12, 3, 6, 2, 6, 4, 8, 6, 6, 2, 15, 1, 6, 3, 8, 6, 6, 3, 12, 3, 6, 4, 9, 2, 6, 6, 9, 2, 9, 3, 13, 3, 6

Offset: 1

Author

N. J. A. Sloane, Nov 02 2008

Keywords

• nonn

Comments

The old entry with this sequence number was a duplicate of A070940.

Crossrefs

Cf. A004016, A093061.

Programs

Mathematica

Table[Total[Mod[Divisors[n],3]],{n,110}] (* Harvey P. Dale, Jan 01 2019 *)
Table[DivisorSum[n,Mod[#,3]&],{n,110}] (* Harvey P. Dale, Jan 09 2022 *)