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%I
%S 3,5,7,11,19,29,47,79,127,191
%N Smallest size (greater than 1) of a topology that cannot be made using n points.
%D K. Ragnarsson and B. E. Tenner, Obtainable sizes of topologies on finite sets, J. Combin. Theory Ser. A 117 (2010) 138-151.
%e There is no topology on 3 points having 7 open sets. However, there do exist topologies on 3 points that have 2, 3, 4, 5 and 6 open sets.
%Y Cf. A137813.
%K nonn
%O 1,1
%A _Bridget Tenner_, Feb 11 2008
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