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%I #5 Oct 24 2017 17:56:54
%S 6,9,15,21,27,33,35,45,51,57,63,65,75,77,87,93,105,111,117,135,141,
%T 143,153,155,161,171,177,183,185,195,201,203,215,231,237,243,245,255,
%U 261,267,273,275,285,287,297,315,321,335,341,351,357,363,371,377,387,393
%N Composite numbers of the form 4 + some prime.
%e a(1)= 4+2(prime)=6 (composite). a(2)= 4+5(prime)=9 (composite). a(3)=4+11(prime) = 15 (composite).
%t Select[4+Prime[Range[100]],CompositeQ] (* _Harvey P. Dale_, Oct 24 2017 *)
%Y Cf. A000040, A002808, A107986, A046132.
%K nonn
%O 1,1
%A _Juri-Stepan Gerasimov_, Aug 14 2009
%E Edited, entries checked, by _R. J. Mathar_, Aug 20 2009