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 A280102 #7 Feb 16 2025 08:33:38 %S A280102 2,5,20,89,809,10704,145989,2054864,19686928,128199160 %N A280102 Engel expansion of e to the base Pi. %H A280102 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/PierceExpansion.html">Pierce Expansion</a> %H A280102 Wikipedia, <a href="http://en.wikipedia.org/wiki/Engel_expansion">Engel Expansion</a> %e A280102 e = Pi/2 + Pi^2/(2*5) + Pi^3/(2*5*20) + Pi^4/(2*5*20*89) + Pi^5/(2*5*20*89*809) + ... %Y A280102 Cf. A232325. %K A280102 nonn,more %O A280102 0,1 %A A280102 _G. C. Greubel_, Dec 25 2016