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 A369395 #14 Jan 29 2024 14:23:36
%S A369395 0,4,432,61696,12300000,3339123264,1195810789376,549031054934016,
%T A369395 315439869711260160,222215334010000000000,188664842745174745939968,
%U A369395 190234762349632291168321536,224946256003775354246877765632,308520390288000443379128425267200,486093585063330330624000000000000000
%N A369395 AGM transform of the even positive numbers.
%C A369395 See A368366 for the definition of the AGM transform.
%H A369395 Paolo Xausa, <a href="/A369395/b369395.txt">Table of n, a(n) for n = 1..210</a>
%t A369395 A369395[n_] := n^n*((n+1)^n - (2*n)!!);
%t A369395 Array[A369395, 15] (* _Paolo Xausa_, Jan 29 2024 *)
%o A369395 (PARI) a369395(n) = {my(v=vector(n,i,i+i)); vecsum(v)^n - n^n*vecprod(v)};
%o A369395 (Python)
%o A369395 from math import factorial
%o A369395 def A369395(n): return n**n*((n+1)**n-(factorial(n)<<n)) # _Chai Wah Wu_, Jan 25 2024
%Y A369395 Cf. A299174, A368366, A368367-A368371, A369394.
%K A369395 nonn,easy
%O A369395 1,2
%A A369395 _Hugo Pfoertner_, Jan 24 2024