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 A349597 #27 Dec 30 2021 14:31:21 %S A349597 3,6,9,27,108,666,6327,88263,1692585,42219558,1318791681 %N A349597 a(n) is the sum of digits of a(n-1)! with a(1) = 3. %F A349597 a(n) = sumdigits(a(n-1)!) for n > 1. %t A349597 nterms=10;NestList[Total[IntegerDigits[#!]]&,3,nterms-1] (* _Paolo Xausa_, Nov 30 2021 *) %Y A349597 Subsequence of A008585. %Y A349597 Cf. A004152. %K A349597 nonn,base,more %O A349597 1,1 %A A349597 _Arkady Pogostkin_, Nov 22 2021 %E A349597 a(10)-a(11) from _Amiram Eldar_, Nov 23 2021