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 A335685 #7 Jul 09 2025 04:53:33 %S A335685 1,18,6570,48697686,7330125946050,22406540276117433798, %T A335685 1390908038123039657933009250,1753405140846978937849992172443469926, %U A335685 44887599350675449085445484460546360180897201250,23336231715157046447023761145710030876842913391344045399558 %N A335685 Main diagonal of A335684. %Y A335685 Cf. A335684. %K A335685 nonn %O A335685 1,2 %A A335685 _N. J. A. Sloane_, Jul 03 2020, based on an email from _Don Knuth_