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 A094873 #7 Aug 07 2023 12:32:07
%S A094873 0,1,2,3,5,6,9,13,17,32,38,44,65,106,125,135,156,178,201,213,278,292,
%T A094873 306,335,350,381,413,446,463,480,570,589,608,647,667,687,728,749,770,
%U A094873 880,996,1020,1044,1169,1247,1300,1327,1354,1437,1551,1669,1699,1760
%N A094873 n! has a triangular number of digits.
%F A094873 {n: A034886(n) in A000217}. - _R. J. Mathar_, Nov 15 2019
%t A094873 Select[Range[0,1800],OddQ[Sqrt[1+8 IntegerLength[#!]]]&] (* _Harvey P. Dale_, Aug 07 2023 *)
%Y A094873 Cf. A000217, A006488.
%K A094873 base,nonn
%O A094873 0,3
%A A094873 _Jason Earls_, Jun 16 2004