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 A361560 #12 Mar 16 2023 04:32:37
%S A361560 1,1,4,47,1471,115042,21591817,9455689609,9464951556046,
%T A361560 21316993121024757,106689322228222150243,1174731578884501228621956,
%U A361560 28221161668500867009724237123,1468937207982284446757761131062629,164682046577167683717133576752582349216,39562388056404531283767850863430043742371123
%N A361560 Number of labeled digraphs on [n] all of whose strongly connected components are complete digraphs.
%H A361560 E. de Panafieu and S. Dovgal, <a href="https://arxiv.org/abs/1903.09454">Symbolic method and directed graph enumeration</a>, arXiv:1903.09454 [math.CO], 2019.
%H A361560 R. W. Robinson, <a href="http://cobweb.cs.uga.edu/~rwr/publications/components.pdf">Counting digraphs with restrictions on the strong components</a>, Combinatorics and Graph Theory '95 (T.-H. Ku, ed.), World Scientific, Singapore (1995), 343-354.
%H A361560 Wikipedia, <a href="https://en.wikipedia.org/wiki/Strongly_connected_component">Strongly connected component</a>
%t A361560 nn = 15; B[n_] := n! 2^Binomial[n, 2]; a[x_] := Exp[x] - 1; Table[B[n], {n, 0, nn}] CoefficientList[Series[1/Normal[Series[Exp[-(Exp[x] - 1)], {x, 0, nn}]] /.
%t A361560 Table[x^i -> z^i/2^Binomial[i, 2], {i, 0, nn}], {z, 0, nn}], z]
%Y A361560 Cf. A011266 (all strong components are cycles), A361527, A003024 (all strong components are singletons).
%K A361560 nonn
%O A361560 0,3
%A A361560 _Geoffrey Critzer_, Mar 15 2023