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%I #15 Sep 05 2016 10:49:47
%S 1,2,5,121,46999,502090394
%N The number of non-isomorphic drawings of the complete graph K_n such that any two edges intersect at most once (a.k.a. "good drawings" or "simple topological graphs").
%D H.-D. O. F. Gronau and H. Harborth, Numbers of nonisomorphic drawings for small graphs, Congressus Numerantium, 71:105-114, 1990.
%D H. Harborth and I. Mengersen, Drawings of the complete graph with maximum number of crossings, Congressus Numerantium, 88:225-228, 1992.
%H B. M. Ábrego, O. Aichholzer, S. Fernández-Merchant, T. Hackl, J. Pammer, A. Pilz, P. Ramos, G. Salazar, and B. Vogtenhuber, <a href="http://www.ist.tugraz.at/cpgg/downloadables/aafhpprsv-agdsc-15.pdf">All Good Drawings of Small Complete Graphs</a>, In Proc. 31st European Workshop on Computational Geometry EuroCG '15, pages 57-60, Ljubljana, Slovenia, 2015.
%H J. Kynčl, <a href="http://dx.doi.org/10.1016/j.ejc.2009.03.005">Enumeration of simple complete topological graphs, European Journal of Combinatorics</a>, 30(7):1676-1685, 2009.
%Y Cf. A000241.
%Y Coincides with A276110 for n <= 5.
%K nonn,more
%O 3,2
%A _Manfred Scheucher_, Aug 18 2016