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 A085878 #4 Dec 05 2013 19:56:18 %S A085878 11,2401,1003003001,38513670001,3200800080004000100001, %T A085878 109572174941077441712143556000001, %U A085878 10000007000002100000350000035000002100000070000001 %N A085878 Smallest n-th power k^n == 1 (mod 10^n), where k>1. %C A085878 Sequence is infinite as (10^n + 1)^n is a candidate, or a(n) < = (10^n +1)^n. %e A085878 a(2) = 49^2= 2401 == 1 (mod 100). %Y A085878 Cf. A085877. %K A085878 nonn %O A085878 1,1 %A A085878 _Amarnath Murthy_, Jul 07 2003 %E A085878 More terms from _Ray Chandler_, Jul 12 2003