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 A344389 #25 Jun 15 2021 14:32:32 %S A344389 1,10,91,739,5275,32491,168571,712891,2345851,5611771,8877691,8877691, %T A344389 8877691,8877691,8877691,8877691,8877691,8877691,8877691,8877691, %U A344389 8877691,8877691,8877691,8877691,8877691,8877691,8877691,8877691,8877691,8877691,8877691,8877691 %N A344389 a(n) is the number of nonnegative numbers < 10^n with all digits distinct. %C A344389 a(n) = a(10) for n > 10 by the pigeonhole principle. %F A344389 a(0) = 1; a(n) = A073531(n) + a(n-1). %Y A344389 Cf. A073531. %K A344389 nonn,base %O A344389 0,2 %A A344389 _Quan Tran_, May 16 2021