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%I A140888 #4 Mar 30 2012 18:52:26
%S A140888 6,13,15,16,18,19,21,17,21,21,22,23,18,22,26,21,22,21,24,24,22,25,22,
%T A140888 22,26,24,22,21,28,23,25,23,25,24,26,25,22,27,27,24,27,22,24,25,23,26,
%U A140888 23,28,23,26,27,26,27,26,27,30,22,26,27,22,25,24,26,29,27,24,27,31,25,26
%N A140888 Number of nonprimes in [210n - 210, 210n] coprime to 210.
%C A140888 For almost all n, a(n) = phi(210) = 48. It first attains this value at a(1751794).
%e A140888 {1,11,13,...,209,} are coprime to 210 in [0, 210]; the nonprimes are {1,121,143,169,187,209} so a(1) = 1.
%o A140888 (PARI) a(n)=sum(k=210*n-210,210*n,gcd(k,210)==1&!isprime(k))
%Y A140888 Cf. A008364, A140887.
%K A140888 nonn,easy,less
%O A140888 1,1
%A A140888 _Juri-Stepan Gerasimov_, Jul 06 2008
%E A140888 Corrected and rewritten by _Charles R Greathouse IV_, Mar 26 2010

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