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 A368010 #16 Dec 11 2023 15:28:34
%S A368010 1,2,1,1,2,3,1,1,1,1,2,3,2,2,1,4,3,4,3,5,4,2,6,5,4,7,3,8,5,2,6,3,7,4,
%T A368010 8,9,6,10,3,9,5,7,11,5,10,12,4,11,13,6,8,14,6,4,12,15,2,5,13,16,7,5,9,
%U A368010 17,18,8,6,10,14,19,20,9,7,6,11,15,21,22,23,10
%N A368010 Ordinal transform of the leading digit of the factorial numbers.
%C A368010 n is the a(n)-th nonnegative integer producing value A008905(n).
%H A368010 Alois P. Heinz, <a href="/A368010/b368010.txt">Table of n, a(n) for n = 0..20000</a>
%F A368010 Ordinal transform of A008905.
%F A368010 a(n) = |{ j in {0..n} : A008905(j) = A008905(n) }|.
%e A368010 a(11) = 3 because 11! = 39916800 is the third factorial with leading digit 3 after 9! = 362880 and 10! = 3628800. A008905(k) = 3 for k = 9, 10, 11, ... .
%Y A368010 Cf. A000142, A008905, A367799.
%K A368010 nonn,look,base
%O A368010 0,2
%A A368010 _Alois P. Heinz_, Dec 07 2023