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 A180725 #11 Oct 05 2019 04:53:10 %S A180725 1,20,3200000,400,512000000000,64000000, %T A180725 703687441776640000000000000000000000000000000000000000000000,8000, %U A180725 900719925474099200000000000000000000000000000000000000000000000000000 %N A180725 Smallest power of 20 that begins with n. %Y A180725 Cf. A009964, A180705, A180726, A180727. %K A180725 nonn,base %O A180725 1,2 %A A180725 _Daniel Mondot_, Sep 18 2010