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 A059080 #6 Jun 14 2013 04:23:58
%S A059080 1,1,1,2,2,0,0,1,6,12,0,0,0,2,52,520,2640,6720,6720,0,0,0,0,25,1770,
%T A059080 53940,1012620,13487040,136745280,1094688000,7025356800,36084787200,
%U A059080 145297152000,435891456000,871782912000,871782912000
%N A059080 Triangle A(n,m) of numbers of n-element T_0-antichains on a labeled m-set, m=0,...,2^n.
%C A059080 An antichain on a set is a T_0-antichain if for every two distinct points of the set there exists a member of the antichain containing one but not the other point. Row sums give A059079. Column sums give A059083.
%D A059080 V. Jovovic and G. Kilibarda, On the number of Boolean functions in the Post classes F^{mu}_8, Diskretnaya Matematika, 11 (1999), no. 4, 127-138 (translated in Discrete Mathematics and Applications, 9, (1999), no. 6)
%D A059080 V. Jovovic, G. Kilibarda, On enumeration of the class of all monotone Boolean functions, in preparation.
%H A059080 V. Jovovic, <a href="/A059080/a059080.pdf">3-element T_0-antichains on a labeled 4-set</a>
%H A059080 V. Jovovic, <a href="/A059083/a059083.pdf">Formula for the number of m-element T_0-antichains on a labeled n-set</a>
%e A059080 [1, 1], [1, 2, 2], [0, 0, 1, 6, 12], [0, 0, 0, 2, 52, 520, 2640, 6720, 6720], ...; there are 2 3-element T_0-antichains on a 3-set: {{1}, {2}, {3}}, {{1, 2}, {1, 3}, {2, 3}}.
%Y A059080 Cf. A059079, A059081-A059083, A059048-A059052.
%K A059080 nonn
%O A059080 0,4
%A A059080 _Vladeta Jovovic_, Goran Kilibarda, Dec 29 2000