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%I #12 Feb 24 2023 12:00:47
%S 1,1,1,1,2,2,2,2,2,2,3,3,3,3,3,3,3,3,4,4,4,4,4,4,4,4,4,5,5,5,5,5,5,5,
%T 5,5,5,6,6,6,6,6,6,6,6,6,6,6,6,7,7,7,7,7,7,7,7,7,7,7,7,7,7,8,8,8,8,8,
%U 8,8,8,8,8,8,8,8,8,8,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9
%N n appears n-th composite number times.
%C n appears A002808(n) times.
%t Module[{nn=20,comps,len},comps=Select[Range[nn],CompositeQ];len=Length[ comps];Flatten[Table[#[[1]],{#[[2]]}]&/@Thread[{Range[len],comps}]]] (* _Harvey P. Dale_, Aug 17 2014 *)
%Y Cf. A002808, A111653, A111655.
%K easy,less,nonn
%O 1,5
%A _Jonathan Vos Post_, Aug 12 2005
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