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%I #16 Aug 17 2022 15:35:19
%S 1,1,1,1,2,1,1,4,3,1,1,6,9,4,1,1,10,25,18,5,1,1,14,70,85,31,6,1,1,21,
%T 217,832,288,51,7,1
%N Triangle T(n,k) giving number of nonisomorphic loopless matroids of rank k on n labeled points (n >= 1, 1<=k<=n).
%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="http://www.stp.dias.ie/~dukes/phd.html">Counting and Probability in Matroid Theory</a>, Ph.D. Thesis, Trinity College, Dublin, 2000.
%H <a href="/index/Mat#matroid">Index entries for sequences related to matroids</a>
%H W. M. B. Dukes, <a href="http://arXiv.org/abs/math.CO/0411557">On the number of matroids on a finite set</a>
%e 1;
%e 1, 1;
%e 1, 2, 1;
%e 1, 4, 3, 1;
%e 1, 6, 9, 4, 1;
%e 1, 10, 25, 18, 5, 1;
%e 1, 14, 70, 85, 31, 6, 1;
%e 1, 21, 217, 832, 288, 51, 7, 1;
%e ...
%Y Cf. A058716 (same except for border), A058710, A058711.
%Y Row sums give A058718. Diagonals give A000065, A058719.
%K nonn,tabl,nice
%O 1,5
%A _N. J. A. Sloane_, Dec 31 2000
%E Corrected and extended by _Jean-François Alcover_, Oct 21 2013
%E Reverted to original data by _Jean-François Alcover_, Aug 17 2022
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