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%I #12 Apr 15 2023 05:17:42
%S 0,0,0,0,0,0,0,1,0,1,0,2,0,2,1,2,0,3,0,4,2,4,0,4,1,4,3,5,0,7,0,6,4,6,
%T 3,7,0,6,4,6,0,8,0,8,7,8,0,10,2,10,6,10,0,12,5,10,6,10,0,12,0,10,8,10,
%U 5,14,0,12,8,15,0,16,0,13,12,14,6,19,0,17,10,15,0,19,7,15,10,15,0,19,6,16
%N Number of triprimes less than or equal to and not coprime to n.
%o (PARI) a(n) = sum(k=1, n, if (bigomega(k) == 3, gcd(k,n) != 1)); \\ _Michel Marcus_, Apr 15 2023
%Y Cf. A000010, A014612, A144741.
%K easy,nonn
%O 1,12
%A _Reikku Kulon_, Sep 20 2008
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