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 A346317 #7 Jul 15 2021 04:31:01
%S A346317 1,3,11,40,148,560,2160,8448,33344,132352,527104,2103296,8401920,
%T A346317 33583104,134279168,537001984,2147762176,8590524416,34360983552,
%U A346317 137441574912,549761318912,2199034789888,8796117139456,35184422420480,140737593212928,562950171525120
%N A346317 Number of permutations of [n] having two cycles of the form (c1, c2, ..., c_m) where c1 = min_{i>=1} c_i and c_j = min_{i>=j} c_i or c_j = max_{i>=j} c_i.
%H A346317 Alois P. Heinz, <a href="/A346317/b346317.txt">Table of n, a(n) for n = 2..1000</a>
%H A346317 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (8,-20,16).
%F A346317 G.f.: (4*x^3-7*x^2+5*x-1)*x^2/((4*x-1)*(2*x-1)^2).
%F A346317 For n>2, a(n) = 2^(2*n-5) + (n-1)*2^(n-4). - _Vaclav Kotesovec_, Jul 15 2021
%Y A346317 Column k=2 of A344855.
%K A346317 nonn,easy
%O A346317 2,2
%A A346317 _Alois P. Heinz_, Jul 13 2021