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 A203228 #13 Dec 15 2016 23:49:24
%S A203228 1,3,20,492,59328,42750720,215488512000,8688622215168000,
%T A203228 3152932286024908800000,11441362514460661304524800000,
%U A203228 456702585875829909265192058880000000,218761269624450195162273767321763840000000000
%N A203228 (n-1)-st elementary symmetric function of (1!,...,(n-1)!).
%F A203228 From _Daniel Suteu_, Dec 04 2016: (Start)
%F A203228 a(n) ~ (e-1) * A000178(n).
%F A203228 a(1) = 1, a(n) = n! * a(n-1) + A000178(n-1). (End)
%t A203228 f[k_] := k!; t[n_] := Table[f[k], {k, n}]
%t A203228 a[n_] := SymmetricPolynomial[n - 1, t[n]]
%t A203228 Table[a[n], {n, 14}] (* A203228 *)
%Y A203228 Cf. A000142, A203222.
%K A203228 nonn
%O A203228 1,2
%A A203228 _Clark Kimberling_, Dec 30 2011