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Least integer m such that there are at least n composite numbers between m and 2*m.
0

%I #3 Mar 30 2012 18:50:45

%S 2,3,4,5,6,8,8,11,12,13,14,14,17,18,18,20,20,23,24,25,26,28,29,30,32,

%T 32,33,35,38,38,39,41,42,43,44,44,46,47,48,48,50,53,54,56,58,59,60,60,

%U 61,62,62,63,65,67,68,68,71,72,72,73,74,74,77,78,80,80,81,83,84,85,86,88

%N Least integer m such that there are at least n composite numbers between m and 2*m.

%C a(n) = Min{m: n <= #{x composite: m<=x<=2*m}}.

%Y Cf. A059316, A002808.

%K nonn

%O 1,1

%A _Reinhard Zumkeller_, Aug 25 2004