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 A094545 #14 Feb 16 2025 08:32:53
%S A094545 1,1,1,4,17,176,2287,49540,1518337,67457584,4254836111,376795261844,
%T A094545 46709151254449,8061849904932136,1936383997541071639,
%U A094545 646603398091877815516,300476951799493029958913
%N A094545 Number of minimal T_0-covers of an n-set.
%C A094545 A cover of a set is a T_0-cover if for every two distinct points of the set there exists a member (block) of the cover containing one but not the other point.
%C A094545 Row sums of A094544.
%H A094545 Goran Kilibarda and Vladeta Jovovic, <a href="https://arxiv.org/abs/1411.4187">Enumeration of some classes of T_0-hypergraphs</a>, arXiv:1411.4187 [math.CO], 2014.
%H A094545 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/MinimalCover.html">Minimal Cover</a>.
%F A094545 a(n) = Sum_{m=0..n} (n!/m!)*binomial(2^m-m-1, n-m).
%F A094545 a(n) = Sum_{m=0..n} Stirling1(n, m)*A046165(m).
%F A094545 E.g.f.: Sum_{n>=0} x^n*(1+x)^(2^n-n-1)/n!.
%Y A094545 Cf. A035348, A046165, A094544, A094546.
%K A094545 easy,nonn
%O A094545 0,4
%A A094545 Goran Kilibarda and _Vladeta Jovovic_, May 08 2004