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 A216140 #19 Oct 01 2012 23:37:55
%S A216140 38,64,38,23,21,23,38,32,2,17,17,13,88,18,32,24,23,11,2,60,52,26,17,
%T A216140 23,43,32,16,31,2,24,25,17,19,17,21,16,37,16,2,36,31,10,30,42,39,19,
%U A216140 17,11,2,11,14,35,25,30,20,23,25,24,2,27,26,31,38,30,30,17,8
%N A216140 Conjectured number of digits in highest power of n with no two consecutive identical digits.
%C A216140 Number of digits in n^k is equal to A055642(n^k) = floor(1+k*log_10(n)). - _V. Raman_, Sep 27 2012
%H A216140 V. Raman and T. D. Noe, <a href="/A216140/b216140.txt">Table of n, a(n) for n = 2..1000</a> (terms 2 to 99 are from V. Raman)
%t A216140 Table[mx = 0; Do[If[! MemberQ[Differences[d = IntegerDigits[n^k]], 0], mx = Length[d]], {k, 1000}]; mx, {n, 2, 50}] (* _T. D. Noe_, Oct 01 2012 *)
%Y A216140 Cf. A216063, A216064, A216065.
%K A216140 nonn,base
%O A216140 2,1
%A A216140 _V. Raman_, Sep 01 2012