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%I #21 Jun 06 2022 05:47:22
%S 1,0,1,1,0,0,2,0,1,0,0,1,2,0,0,1,0,0,2,0,2,0,0,0,1,0,1,2,0,0,2,0,0,0,
%T 0,1,2,0,2,0,0,0,2,0,0,0,0,1,0,0,0,2,0,0,0,0,2,0,0,0,2,0,2,1,0,0,2,0,
%U 0,0,0,0,2,0,1,2,0,0,2,0,1,0,0,2,0,0,0,0,0,0,1,0,2,0,0,0,2,0,0,1,0,0,2,0,0
%N a(n) = sigma(n) mod 3.
%H Antti Karttunen, <a href="/A074941/b074941.txt">Table of n, a(n) for n = 1..16384</a>
%F a(n) = A010872(A000203(n)). - _Antti Karttunen_, Nov 05 2017
%p A074941:= n-> (numtheory[sigma](n) mod 3):
%p seq (A074941(n), n=1..105); # _Jani Melik_, Jan 26 2011
%t a[n_] := Mod[DivisorSigma[1, n], 3]; Array[a, 100] (* _Amiram Eldar_, Jun 06 2022 *)
%o (PARI) a(n)=sigma(n)%3
%Y Cf. A000203, A010872.
%Y Differs from A002324 for the first time at n=49, where a(49) = 0, while A002324(49) = 3.
%K easy,nonn
%O 1,7
%A _Benoit Cloitre_, Oct 04 2002
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