This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A332813 #13 Mar 01 2020 20:46:05
%S A332813 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 A332813 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 A332813 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 A332813 a(n) = A048675(n) mod 3.
%C A332813 Completely additive modulo 3.
%C A332813 See comments in A332823 which is 0,+1,-1 version of this sequence.
%H A332813 Antti Karttunen, <a href="/A332813/b332813.txt">Table of n, a(n) for n = 1..65537</a>
%H A332813 <a href="/index/Pri#prime_indices">Index entries for sequences computed from indices in prime factorization</a>
%F A332813 a(n) = A010872(A048675(n)).
%F A332813 a(A332461(n)) = a(A332462(n)) = A329903(n).
%o A332813 (PARI) A332813(n) = { my(f = factor(n)); (sum(k=1, #f~, f[k, 2]*2^primepi(f[k, 1]))/2)%3; };
%Y A332813 Cf. A010872, A048675, A332461, A332462.
%Y A332813 Cf. A332823 (for 0,+1,-1 version of this sequence).
%Y A332813 Cf. A332820, A332821, A332822 for positions of 0's, 1's and 2's in this sequence.
%Y A332813 Cf. also A329903.
%K A332813 nonn
%O A332813 1,3
%A A332813 _Antti Karttunen_, Mar 01 2020