This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A058716 #42 Sep 06 2023 22:42:31 %S A058716 1,0,1,0,1,1,0,1,2,1,0,1,4,3,1,0,1,6,9,4,1,0,1,10,25,18,5,1,0,1,14,70, %T A058716 85,31,6,1,0,1,21,217,832,288,51,7,1 %N A058716 Triangle T(n,k) giving number of nonisomorphic loopless matroids of rank k on n labeled points (n >= 0, 0 <= k <= n). %H A058716 W. M. B. Dukes, <a href="http://www.stp.dias.ie/~dukes/matroid.html">Tables of matroids</a>. %H A058716 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 A058716 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 A058716 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 A058716 <a href="/index/Mat#matroid">Index entries for sequences related to matroids</a> %e A058716 Triangle T(n,k) (with rows n >= 0 and columns k >= 0) begins as follows: %e A058716 1; %e A058716 0, 1; %e A058716 0, 1, 1; %e A058716 0, 1, 2, 1; %e A058716 0, 1, 4, 3, 1; %e A058716 0, 1, 6, 9, 4, 1; %e A058716 0, 1, 10, 25, 18, 5, 1; %e A058716 0, 1, 14, 70, 85, 31, 6, 1; %e A058716 0, 1, 21, 217, 832, 288, 51, 7, 1; %e A058716 ... %Y A058716 Cf. A058717 (same except for border), A058710, A058711. Row sums give A058718. Diagonals give A000065, A058719. %K A058716 nonn,tabl,nice,hard %O A058716 0,9 %A A058716 _N. J. A. Sloane_, Dec 31 2000 %E A058716 Corrected and extended by _Jean-François Alcover_, Oct 21 2013 %E A058716 Reverted to original data by _Sean A. Irvine_, Aug 16 2022