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a(n) = A048675(n) mod 3.
6

%I #13 Mar 01 2020 20:46:05

%S 0,1,2,2,1,0,2,0,1,2,1,1,2,0,0,1,1,2,2,0,1,2,1,2,2,0,0,1,2,1,1,2,0,2,

%T 0,0,2,0,1,1,1,2,2,0,2,2,1,0,1,0,0,1,2,1,2,2,1,0,1,2,2,2,0,0,0,1,1,0,

%U 0,1,2,1,1,0,1,1,0,2,2,2,2,2,1,0,2,0,1,1,2,0,1,0,0,2,0,1,1,2,2,1,2,1,1,2,2

%N a(n) = A048675(n) mod 3.

%C Completely additive modulo 3.

%C See comments in A332823 which is 0,+1,-1 version of this sequence.

%H Antti Karttunen, <a href="/A332813/b332813.txt">Table of n, a(n) for n = 1..65537</a>

%H <a href="/index/Pri#prime_indices">Index entries for sequences computed from indices in prime factorization</a>

%F a(n) = A010872(A048675(n)).

%F a(A332461(n)) = a(A332462(n)) = A329903(n).

%o (PARI) A332813(n) = { my(f = factor(n)); (sum(k=1, #f~, f[k, 2]*2^primepi(f[k, 1]))/2)%3; };

%Y Cf. A010872, A048675, A332461, A332462.

%Y Cf. A332823 (for 0,+1,-1 version of this sequence).

%Y Cf. A332820, A332821, A332822 for positions of 0's, 1's and 2's in this sequence.

%Y Cf. also A329903.

%K nonn

%O 1,3

%A _Antti Karttunen_, Mar 01 2020