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 A016065 #21 Sep 08 2022 08:44:40
%S A016065 1,3,15,159,3039,89439,3718239,206931039,14838252639,1331657196639,
%T A016065 146181741036639,19266392807916639,3002019319241196639,
%U A016065 545863051930098156639,114546679900210059756639,27474742723487400843756639,7469448066579203294091756639,2284713285166428266627979756639
%N A016065 a(n) = Sum_{k=0..n} k!*(k+1)!.
%C A016065 Partial sums of A010790. - _Sean A. Irvine_, Jan 02 2019
%H A016065 Seiichi Manyama, <a href="/A016065/b016065.txt">Table of n, a(n) for n = 0..252</a>
%t A016065 Table[Sum[k! (k+1)!, {k, 0, n}], {n, 0, 20}] (* _Vincenzo Librandi_, Jan 02 2019 *)
%o A016065 (PARI) a(n) = sum(k=0, n, k!*(k+1)!); \\ _Michel Marcus_, Jan 02 2019
%o A016065 (Magma) [&+[ Factorial(k)*Factorial(k+1): k in [0..n]]: n in [0..18]]; // _Vincenzo Librandi_, Jan 02 2019
%Y A016065 Cf. A010790.
%K A016065 nonn
%O A016065 0,2
%A A016065 _Robert G. Wilson v_
%E A016065 More terms from _Vincenzo Librandi_, Jan 02 2019