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A074941 a(n) = sigma(n) mod 3. 8

%I

%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

%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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Last modified April 19 13:00 EDT 2021. Contains 343114 sequences. (Running on oeis4.)