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 A059079 #7 Jun 14 2013 04:17:11 %S A059079 2,5,19,16654,2369110564675,5960531437586238714806902334250676, %T A059079 479047836152505670895481840783987408043359908583921478726185296900312296071642855730299 %N A059079 Number of n-element T_0-antichains on a labeled set. %C A059079 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. %D A059079 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 A059079 V. Jovovic, G. Kilibarda, On enumeration of the class of all monotone Boolean functions, in preparation. %H A059079 Vladeta Jovovic, <a href="/A059079/a059079.pdf">Illustration</a> %e A059079 a(0) = (1/0!)*[1!*e] = 2; a(1) = (1/1!)*[2!*e] = 5; a(2) = (1/2!)*([4!*e] - 2*[3!*e] + [2!*e]) = 19; a(3) = (1/3!)*([8!*e] - 6*[6!*e] + 6*[5!*e] + 3*[4!*e] - 6*[3!*e] + 2*[2!*e]) = 16654, where [n!*e]=floor(n!*exp(1)). %Y A059079 Cf. A059080-A059083, A059048-A059052, A000522. %K A059079 hard,nonn %O A059079 0,1 %A A059079 _Vladeta Jovovic_, Goran Kilibarda, Dec 23 2000