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 A005806 M2072 #30 Mar 24 2023 18:05:30 %S A005806 1,1,1,2,14,546,169444,560043206 %N A005806 Number of comparative probability orderings on n elements. %D A005806 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). %H A005806 Andrew Beveridge, Ian Calaway, and Kristin Heysse, <a href="https://arxiv.org/abs/1912.12319">de Finetti Lattices and Magog Triangles</a>, arXiv:1912.12319 [math.CO], 2019. %H A005806 T. Fine and J. Gill, <a href="https://doi.org/10.1214/aop/1176996036">The enumeration of comparative probability relations</a>, Ann. Prob. 4 (1976) 667-673. %H A005806 D. Maclagan, <a href="https://arxiv.org/abs/math/9809134">Boolean Term Orders and the Root System B_n</a>, arXiv:math/9809134 [math.CO], 1998-1999. %H A005806 D. Maclagan, <a href="https://doi.org/10.1023/A:1006207716298">Boolean Term Orders and the Root System B_n</a>, Order 15 (1999), 279-295. %F A005806 a(n) >= A009997(n) with equality iff n < 5. - _M. F. Hasler_, Mar 17 2023 %e A005806 For n = 3, the two orders are 1 < 2 < 12 < 3 < 13 < 23 < 123 and 1 < 2 < 3 < 12 < 13 < 23 < 123. %e A005806 For zero elements, there is exactly one ordering. - _M. F. Hasler_, Mar 17 2023 %Y A005806 Cf. A009997. %K A005806 nonn,nice,hard,more %O A005806 0,4 %A A005806 _N. J. A. Sloane_ %E A005806 a(7) from Diane Maclagan and _Michael Kleber_