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%I #9 Dec 25 2015 21:04:18
%S 0,1,3,8,11,14,17,20,23,30,37,41,52,56,60,64,68,72,76,89,93,97,106,
%T 110,119,128,132,137,146,155,164,169,178,183,197,202,216,221,226,231,
%U 260,265,270,275,280,285,290,295,300,331,336,341,346,351,367,372,377,393,398,403,414,419,435,440,451,456,467,472,483,494,499,510
%N Numbers n for which (2n+1)! / n! [= A000407(n)] is >= k! but < 2*k! for some k; positions of ones in A265891.
%C a(0) = 0 is a special case in this sequence, thus the indexing starts from zero.
%C Numbers n such that A000407(n) is in A265334.
%H Antti Karttunen, <a href="/A265897/b265897.txt">Table of n, a(n) for n = 0..845</a>
%Y Cf. A000407, A265891, A265334.
%Y Cf. also A265898.
%K nonn
%O 0,3
%A _Antti Karttunen_, Dec 24 2015