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%I #12 Sep 27 2012 11:21:43
%S 4,8,9,10,14,15,16,20,21,22,30,38,39,40,44,45,46,54,55,56,57,58,62,63,
%T 64,65,66,72,80,81,82,90,91,92,93,94,95,96,102,108,114,115,116,117,
%U 118,119,120,121,122,123,124,125,126,132,133,134,135,136
%N Composite numbers that are in the gap between an even-indexed prime and an odd-indexed prime.
%e Illustration of initial terms of three sequences:
%e A210998: 4, 8, 9, 10, 14, 15, 16
%e A000040: 2, 3, 5, 7, 11, 13,
%e A210999: 6, 12,
%t Select[Range[4, 200], Not[PrimeQ[#]] && EvenQ[PrimePi[#]] &] (* _Alonso del Arte_, Sep 26 2012 *)
%Y Cf. A002808, A014689, A031215, A031368, A073170, A210999.
%K nonn,easy
%O 1,1
%A _Omar E. Pol_, Sep 26 2012
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