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%I #6 Jun 12 2018 12:11:09
%S 1,1,1,1,1,3,17,489,28103,2866895
%N Number of crossing-maximal order types of n points in the plane.
%H Alexander Pilz and Emo Welzl, <a href="http://drops.dagstuhl.de/opus/volltexte/2015/5119/">Order on order types</a>, Discrete & Computational Geometry, 59 (No. 4, 2015), 886-922.
%Y Cf. A006247, A305376.
%K nonn,more
%O 1,6
%A _N. J. A. Sloane_, Jun 12 2018