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 A055532 #7 Mar 16 2021 08:30:18 %S A055532 6,108,2310,65700,2583126,142259628,11012710470,1196543891700, %T A055532 181782466114326,38435786111785788,11256358984173551430 %N A055532 Number of labeled order relations on n nodes in which longest chain has 3 nodes. %D A055532 L. Comtet, Advanced Combinatorics, Reidel, 1974, p. 60. %Y A055532 A column or diagonal of triangle in A342587. %K A055532 nonn %O A055532 3,1 %A A055532 _N. J. A. Sloane_, Jul 10 2000 %E A055532 Extended to n=13 by _Brendan McKay_, Mar 16 2021