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%I #5 Mar 30 2012 17:22:57
%S 0,1,0,1,2,2,2,3,2,2,3,3,3,3,2,3,4,4,5,5,4,5,5,5,5,6,6,6,6,6,5,6,5,6,
%T 7,7,7,8,8,9,9,9,8,9,9,9,10,10,9,10,9,9,10,10,10,11,11,12,12,12,12,12,
%U 11,12,13,13,13,14,13,13,14,14,13,13,12,13,13,13,12,13,13,14,14,14,15,16,15,15,15,15,15,15,14,14,15,15,16,17,16,16
%N The number of lucky numbers between n and 2n, exclusive.
%C There is a lucky number between n and 2n for all n >= 4. There are at least n lucky numbers between x/2 and x for all x >= A186234(n).
%Y Cf. A000959 (lucky numbers)
%K nonn
%O 1,5
%A _T. D. Noe_, Feb 15 2011