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 A173324 #18 Nov 21 2024 19:53:16
%S A173324 4,4,7,19,73,361,2161,15121,120961,1088641,10886401,119750401,
%T A173324 1437004801,18681062401,261534873601,3923023104001,62768369664001,
%U A173324 1067062284288001,19207121117184001,364935301226496001,7298706024529920001,153272826515128320001
%N A173324 a(n) = 3*n! + 1.
%H A173324 Vincenzo Librandi, <a href="/A173324/b173324.txt">Table of n, a(n) for n = 0..200</a>
%F A173324 a(0) = 4, a(n) = n*a(n-1)-n+1 for n>0. - _Sergei N. Gladkovskii_, Jul 04 2012
%p A173324 a:= proc(n) if n=0 then 4 else a(n):= n*a(n-1)-n+1 fi end: seq (a(n), n=0..25); # _Sergei N. Gladkovskii_, Jul 04 2012
%t A173324 Table[3 n! + 1, {n, 0, 30}] (* _Vincenzo Librandi_, Sep 29 2013 *)
%o A173324 (Magma) [3*Factorial(n) + 1: n in [0..25]]; // _Vincenzo Librandi_, Sep 29 2013
%o A173324 (Magma) [4] cat [n eq 1 select n+3 else n*Self(n-1)-n+1: n in [1..25] ]; // _Vincenzo Librandi_, Sep 29 2013
%Y A173324 Cf. sequences of the type k*n!+1: A038507 (k=1), A052898 (k=2), this sequence, A173322 (k=4), A173319 (k=5), A173314 (k=6).
%K A173324 nonn,easy
%O A173324 0,1
%A A173324 _Vincenzo Librandi_, Feb 16 2010