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 A182430 #10 Jan 25 2023 14:19:03
%S A182430 1,0,0,1,8,56,408,3228,28032,267264,2787840,31662720,389560320,
%T A182430 5166650880,73528680960,1118124000000,18098712576000,310759981056000,
%U A182430 5642339254272000,108022399414272000,2175029897822208000
%N A182430 a(n) = n! - A003149(n-1).
%C A182430 a(n) is the number of fixed points over all permutations of {1,2,...,n} that are not strong fixed points. Definition by Emeric Deutsch in A003149: a permutation p of {1,2,...,n} is said to have j as a strong fixed point (splitter) if p(k)<j for k<j and p(k)>j for k>j.
%F A182430 O.g.f.: (1-x-I(x))/(1-I(x))^2 where I(x) is the o.g.f. for A003319.
%e A182430 a(4)=8 because we have: 1_43'2, 243'1, 32'1_4, 32'41, 413'2, 42'13, 42'3'1. The permutations are given in one line notation. The components are separated by _ and the fixed points that are not splitters are marked by '.
%t A182430 nn = 20; p = Sum[n! x^n, {n, 0, nn}]; i = 1 - 1/p; CoefficientList[Series[p - x/(1 - i)^2, {x, 0, nn}], x]
%Y A182430 Cf. A003149, A003319.
%K A182430 nonn
%O A182430 0,5
%A A182430 _Geoffrey Critzer_, Apr 28 2012