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%I #5 Dec 05 2013 19:55:36
%S 1,4,9,6,15,8,21,10,25,12,27,14,33,16,35,18,39,20,45,22,49,24,51,26,
%T 55,28,57,30,63,32,65,34,69,36,75,38,77,40,81,42,85,44,87,46,91,48,93,
%U 50,95,52,99,54,105,56,111,58,115,60,117,62,119,64,121,66
%N a(1) = 1 and then alternately even and odd composite numbers matching the parity of the index.
%t Module[{nn=150,comps,odds,evens,len},comps=Complement[Range[nn], Prime[Range[ PrimePi[nn]]]]; odds=Select[ comps, OddQ];evens=Select[comps,EvenQ]; len=Min[ Length[odds],Length[evens]]; Riffle[Take[odds,len],Take[evens,len]]] (* _Harvey P. Dale_, Feb 19 2013 *)
%Y Cf. A075066.
%K easy,nonn
%O 1,2
%A _Amarnath Murthy_, Sep 08 2002
%E More terms from _Harvey P. Dale_, Feb 19 2013
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