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 A338973 #20 Dec 26 2020 23:42:46 %S A338973 1,2,3,4,5,6,7,8,9,10,11,13,14,15,16,18,19,20,22,23,24,26,27,29,30,31, %T A338973 33,34,36,37,39,41,42,44,45,47,48,50,52,53,55,57,58,60,62,63,65,67,68, %U A338973 70,72,74,75,77,79,81,82,84,86,88,90,91,93,95,97,99,101,102 %N A338973 Possible number of digits in a factorial. %C A338973 This is A034886 with duplicate terms removed. %F A338973 a(n) = A034886(n+3) for n>=4. %t A338973 DeleteDuplicates @ IntegerLength[Range[71]!] (* _Amiram Eldar_, Dec 24 2020 *) %Y A338973 Cf. A000142, A034886. %K A338973 nonn,base %O A338973 1,2 %A A338973 _Christian Amet_, Dec 18 2020