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 A059577 #7 Sep 29 2022 02:17:17 %S A059577 1,4,87,4239,385422,56304887,12069075787,3566873953872, %T A059577 1389853778362041,690363881963396569,425768137345317003930, %U A059577 319198739428765958327137,285884881894650500659218725,301473688731974642805982034540,369723877220104937359593829963363 %N A059577 Main diagonal of the array A059574. %K A059577 easy,nonn %O A059577 1,2 %A A059577 _Floor van Lamoen_, Jan 23 2001 %E A059577 More terms from _Sean A. Irvine_, Sep 29 2022