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 A325304 #17 Feb 16 2025 08:33:58 %S A325304 1,1,0,1,0,2,0,1,5,0,1,20,0,1,16,95,0,1,22,830,0,1,29,790,10297,0,1, %T A325304 37,1479,259563,0,1,46,2625,166988,11546911 %N A325304 Irregular triangle read by rows: T(n,k) is the number of simple connected graphs on n unlabeled nodes with matching number k, (0 <= k <= floor(n/2)). %H A325304 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/MatchingNumber.html">Matching Number</a> %H A325304 Wikipedia, <a href="https://en.wikipedia.org/wiki/Matching_(graph_theory)">Matching (graph theory)</a> %F A325304 T(2*n, n) = A218463(n). %e A325304 Triangle begins: %e A325304 1; %e A325304 1; %e A325304 0, 1; %e A325304 0, 2; %e A325304 0, 1, 5; %e A325304 0, 1, 20; %e A325304 0, 1, 16, 95; %e A325304 0, 1, 22, 830; %e A325304 0, 1, 29, 790, 10297; %e A325304 0, 1, 37, 1479, 259563; %e A325304 0, 1, 46, 2625, 166988, 11546911; %e A325304 ... %Y A325304 Columns k=2..3 are A243800, A243801. %Y A325304 Row sums are A001349. %Y A325304 Cf. A286951 (not necessarily connected). %Y A325304 Cf. A218463 (right diagonal, even terms). %Y A325304 Cf. A263341, A294490. %K A325304 nonn,tabf,more %O A325304 0,6 %A A325304 _Andrew Howroyd_, Sep 05 2019