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%I #6 Oct 04 2012 10:51:25
%S 1,1,1,2,3,2,3,2,3,3,4,2,3,4,2,3,3,6,3,3,3,2,4,4,4,3,5,2,4,4,4,4,4,3,
%T 3,4,2,5,5,4,3,4,4,2,6,5,5,3,4,1,6,3,4,2,5,4,4,5,4,4,5,6,1,5,5,5,3,3,
%U 5,3,5,3,6,5,4,4,3,5,4,1,5,4,5,7,3,5,5,5,4,1,3,4,5,3,5,4,4,5,4,6,4,5,3,6,6
%N Number of nonprimes in [30n - 30, 30n] coprime to 30.
%C For almost all n, a(n) = phi(30) = 8. It first attains this value at a(361).
%e {1,7,11,13,17,19,23,29} are coprime to 30 in [0, 30]; 1 is nonprime, so a(1) = 1.
%e {31,37,41,43,47,49,53,59} are coprime to 30 in [30, 60]; 49 is nonprime, so a(2) = 1.
%t Table[Count[Range[30n-30,30n],_?(CoprimeQ[#,30]&&!PrimeQ[#]&)],{n,110}] (* _Harvey P. Dale_, Oct 04 2012 *)
%Y Cf. A007775.
%K nonn,easy,less
%O 1,4
%A _Juri-Stepan Gerasimov_, Jul 06 2008
%E Rewritten and extended by _Charles R Greathouse IV_, Mar 26 2010