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 A085877 #6 Dec 05 2013 19:56:18 %S A085877 81,2401,62001,1560001,351600001,47852000001,610350000001, %T A085877 586547900000001,5508423000000001,2032852170000000001, %U A085877 184259414700000000001,26756525040000000000001,26756525040000000000001 %N A085877 Smallest square k^2 == 1 (mod 10^n) where k > 1. %C A085877 Sequence is infinite as (10^n + 1)^2 is a candidate, i.e. a(n) < = (10^n +1)^2. %F A085877 a(n) = A181539(n)^2. %Y A085877 Cf. A085878. %K A085877 nonn %O A085877 1,1 %A A085877 _Amarnath Murthy_, Jul 07 2003 %E A085877 Corrected and extended by _Ray Chandler_, Jul 09 2003