%I #11 Oct 11 2019 06:28:13
%S 1,15,171,2053,33442,1022217
%N Number of matroids of rank 3 on n labeled points.
%H W. M. B. Dukes, <a href="http://www.stp.dias.ie/~dukes/matroid.html">Tables of matroids</a>.
%H W. M. B. Dukes, <a href="https://web.archive.org/web/20030208144026/http://www.stp.dias.ie/~dukes/phd.html">Counting and Probability in Matroid Theory</a>, Ph.D. Thesis, Trinity College, Dublin, 2000.
%H W. M. B. Dukes, <a href="https://arxiv.org/abs/math/0411557">The number of matroids on a finite set</a>, arXiv:math/0411557 [math.CO], 2004.
%H W. M. B. Dukes, <a href="http://emis.impa.br/EMIS/journals/SLC/wpapers/s51dukes.html">On the number of matroids on a finite set</a>, Séminaire Lotharingien de Combinatoire 51 (2004), Article B51g.
%H <a href="/index/Mat#matroid">Index entries for sequences related to matroids</a>
%Y Column k=3 of A058669.
%K nonn
%O 3,2
%A _N. J. A. Sloane_, Dec 30 2000