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%I #4 Mar 30 2012 18:52:40
%S 1,4,4,4,4,6,6,6,6,6,6,8,8,8,8,8,8,8,8,9,9,9,9,9,9,9,9,9,10,10,10,10,
%T 10,10,10,10,10,10,12,12,12,12,12,12,12,12,12,12,12,12,14,14,14,14,14,
%U 14,14,14,14,14,14,14,14,14,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15
%N n-th nonprime number appears n-th nonprime numbers times.
%C A018252(n) appears A018252(n) times; 1 appears once, n-th composite number appears n-th composite number times; 1 together with A111655.
%F a(1)=1, a(n+1)=A111655(n).
%Y Cf. A063905, A141468, A175944.
%K nonn,easy,less
%O 1,2
%A _Juri-Stepan Gerasimov_, Oct 31 2010