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 A063187 #8 Jan 02 2022 21:04:29
%S A063187 1,5,7,12,800,1502,3021,5079,6325,17537,50021,158855,826545,5023575,
%T A063187 5097327,6369490,17535161,19462254,22535278,24898987,55666978,
%U A063187 111142756,305716101,2653533055,3591521863,4889613852,10577043282
%N A063187 Engel expansion of Sum_{k>=0} 1/(4 + k)^k.
%C A063187 Shgz(4) = 1.2309553591249981798150126937918121309...
%t A063187 ToEngel[ x_, n_Integer ] := Rest@First@Transpose@NestList[ {Ceiling[ 1/# ], #}&[ Times@@#-1 ]&, {1, Abs[ x ]+1}, n ]
%Y A063187 Cf. A006784 for definition of Engel expansion.
%K A063187 nonn,easy
%O A063187 1,2
%A A063187 _Olivier Gérard_, Jul 10 2001