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 A309579 #26 Aug 24 2019 20:37:14
%S A309579 2,6,22,102,582,3942,30822,272742,2691942,29303142,348637542,
%T A309579 4499984742,62618845542,934401757542,14882928349542,252007880413542,
%U A309579 4520257017565542,85616990623453542,1707551662741213542,35768179777214173542,785101998295619293542,18019779824218937053542
%N A309579 Maximum principal ratio of a strongly connected digraph on n nodes.
%C A309579 The principal ratio of a strongly connected digraph is the ratio of largest to smallest entries in the stationary distribution of a simple random walk on that digraph.
%H A309579 S. Aksoy, F. Chung, X. Peng, <a href="https://arxiv.org/abs/1602.01162">Extreme values of the stationary distribution of random walks on directed graphs</a>, arXiv:1602.01162 [math.CO], 2016.
%H A309579 S. Aksoy, F. Chung, X. Peng, <a href="https://doi.org/10.1016/j.aam.2016.06.012">Extreme values of the stationary distribution of random walks on directed graphs</a>, Advances in Applied Mathematics, 81:128--155, 2016.
%F A309579 a(n) = (2/3) * (n-1)! * ( n/(n-1) + (1/(n-1)!) * Sum_{i=1..n-3} i! ).
%F A309579 a(n) = 2 * A056199(n-1). - _Alois P. Heinz_, Aug 11 2019
%o A309579 (PARI) a(n) = (2/3) * (n-1)! * ( n/(n-1) + (1/(n-1)!) * sum(i=1, n-3, i!)); \\ _Michel Marcus_, Aug 11 2019
%Y A309579 Cf. A056199.
%K A309579 nonn
%O A309579 3,1
%A A309579 _Sinan G. Aksoy_, Aug 08 2019