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 A050624 #11 Oct 15 2019 11:54:22 %S A050624 1,2,4,13,42,138,458,1525,5081,16936,56451,188168,627226,2090752, %T A050624 6969172,23230574,77435244,258117480,860391598,2867971991,9559906636, %U A050624 31866355454,106221184845,354070616148,1180235387158,3934117957192 %N A050624 Let b(n) = A050623(n) = smallest n-digit number divisible by 3^n; sequence gives b(n)/3^n. %F A050624 a(n) = ceiling(10^(n-1)/3^n). - _Vladeta Jovovic_, Feb 14 2003 %Y A050624 Cf. A050623. %K A050624 nonn,base %O A050624 1,2 %A A050624 _Patrick De Geest_, Jun 15 1999 %E A050624 More terms from _Erich Friedman_, Feb 19 2000