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 A368371 #13 Jan 29 2024 14:24:42 %S A368371 0,4,1016,547856,813732832,3903659417664,67987041960443776, %T A368371 4575641535535493153024,1216334976081196096854162944, %U A368371 1285452910821757852273429343896576,5415346123378152397099190627515485911040,91076602434014222291049466570765323207327092736 %N A368371 AGM transform of powers of 2. %C A368371 See A368366 for further information. %H A368371 Paolo Xausa, <a href="/A368371/b368371.txt">Table of n, a(n) for n = 1..55</a> %t A368371 A369394[n_] := (2^(n+1)-2)^n - n^n*2^(n*(n+1)/2); %t A368371 Array[A369394, 15] (* _Paolo Xausa_, Jan 29 2024 *) %o A368371 (Python) %o A368371 def A368371(n): return ((1<<n+1)-2)**n-n**n*(1<<(n*(n+1)>>1)) # _Chai Wah Wu_, Jan 25 2024 %Y A368371 Cf. A368366. %K A368371 nonn %O A368371 1,2 %A A368371 _N. J. A. Sloane_, Jan 24 2024