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 A050623 #9 Oct 15 2019 11:54:09 %S A050623 3,18,108,1053,10206,100602,1001646,10005525,100009323,1000053864, %T A050623 10000125297,100000190088,1000000837998,10000002002688, %U A050623 100000000895004,1000000037647854,10000000032104772,100000000321047720 %N A050623 Smallest n-digit number divisible by 3^n. %F A050623 a(n) = 3^n*ceiling(10^(n-1)/3^n). - _Vladeta Jovovic_, Feb 14 2003 %Y A050623 Cf. A050621, A050624. %K A050623 nonn,base,easy %O A050623 1,1 %A A050623 _Patrick De Geest_, Jun 15 1999