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%I #11 Jun 17 2024 07:11:50
%S 0,1,0,2,1,1,0,3,0,2,1,2,0,1,1,4,1,1,0,3,0,2,1,3,2,1,0,2,1,2,0,5,1,2,
%T 1,2,0,1,0,4,1,1,0,3,1,2,1,4,0,3,1,2,1,1,2,3,0,2,1,3,0,1,0,6,1,2,0,3,
%U 1,2,1,3,0,1,2,2,1,1,0,5,0,2,1,2,2,1,1,4,1,2,0,3,0,2,1,5,0,1,1,4,1,2,0,3,1
%N Number of primes congruent to 2 modulo 3 dividing n (with multiplicity).
%H Antti Karttunen, <a href="/A373592/b373592.txt">Table of n, a(n) for n = 1..100000</a>
%F a(n) = A001222(A343430(n)).
%F a(n) = A001222(n) - (A007949(n)+A373591(n)).
%F Totally additive with a(3) = 0, a(p) = 1 if p == 2 (mod 3), and a(p) = 0 if p == 1 (mod 3). - _Amiram Eldar_, Jun 17 2024
%t f[p_, e_] := If[Mod[p, 3] == 2, e, 0]; f[3, e_] := 0; a[1] = 0; a[n_] := Plus @@ f @@@ FactorInteger[n]; Array[a, 100] (* _Amiram Eldar_, Jun 17 2024 *)
%o (PARI) A373592(n) = sum(i=1, #n=factor(n)~, (2==n[1, i]%3)*n[2, i]); \\ After code in A083025
%Y Cf. A001222, A343430, A373591.
%Y Cf. also A065339, A083025.
%Y Differs from A257991 for the first time at n=29, where a(29) = 1, while A257991(29) = 0.
%K nonn,changed
%O 1,4
%A _Antti Karttunen_, Jun 13 2024
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