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 A051155 #16 Dec 24 2022 04:53:43
%S A051155 31,1082401,1267650638007162390353805312001,
%T A051155 3273390607896141870013189696827599152293599089395397756694773868291726792119530172040230983402733964346814858022765439290901496446006940490331586560001
%N A051155 a(n) = (2^5^(n+1) - 1)/(2^5^n - 1).
%t A051155 Table[(2^5^(n+1) - 1)/(2^5^n - 1),{n,0,3}] (* _Stefano Spezia_, Dec 23 2022 *)
%Y A051155 Cf. A051154, A051156, A051157.
%K A051155 nonn,easy
%O A051155 0,1
%A A051155 _N. J. A. Sloane_