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%I #14 May 29 2014 22:09:06
%S 6,18,6,24,18,18,12,36,6,36,18,24,12,36,18,42,18,18,12,54,12,36,18,36,
%T 24,36,6,48,18,36,12,54,18,36,36,24,12,36,12,72,18,36,12,54,18,36,18,
%U 42,18,54,18,48,18,18,36,72,12,36,18,54,12,36,12,60,36,36,12,54,18,72,18,36,12
%N 6 * Sum_{d|n} (d mod 3).
%C The old entry with this sequence number was a duplicate of A090331.
%F a(n) = 6*A082909(n). - _Michel Marcus_, May 26 2014
%t Table[6 Sum[Mod[d, 3], {d, Divisors[n]}], {n, 50}] (* _Wesley Ivan Hurt_, May 28 2014 *)
%o (PARI) a(n) = 6*sumdiv(n, d, d % 3); \\ _Michel Marcus_, May 26 2014
%Y Cf. A004016, A082909.
%K nonn,easy
%O 1,1
%A _N. J. A. Sloane_, Nov 02 2008