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 A217177 #8 Oct 03 2012 14:08:38
%S A217177 5,6,5,8,4,6,6,6,3,2,3,11,4,3,5,9,7,7,3,3,2,9,6,9,8,6,12,8,3,9,8,2,4,
%T A217177 4,5,11,4,7,4,9,5,7,2,5,4,4,6,6,4,12,7,6,11,2,7,8,4,8,4,6,4,6,6,4,2,4,
%U A217177 6,8,4,6,14,12,6,12,4,2,6,8,4,6,6,4,10,4,8,12,2
%N A217177 a(n) is the number of digits in the decimal representation of the smallest power of n that contains two consecutive identical digits.
%C A217177 Number of digits in n^k is equal to floor(1 + k*log_10(n)).
%H A217177 V. Raman, <a href="/A217177/b217177.txt">Table of n, a(n) for n = 2..10000</a>
%t A217177 Table[k = 1; While[d = IntegerDigits[n^k]; ! MemberQ[Differences[d], 0], k++];Length[d], {n, 2, 100}] (* _T. D. Noe_, Oct 03 2012 *)
%Y A217177 Cf. A217157, A217167.
%K A217177 nonn,base
%O A217177 2,1
%A A217177 _V. Raman_, Sep 27 2012