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 A158520 #10 Jun 02 2013 13:11:58
%S A158520 0,1,2,3,4,5,6,10,11,12,13,24,25,26,50,51,52,53,103,104,105,106,210,
%T A158520 211,212,422,423,424,425,848,849,850,1698,1699,1700,3399,3400,3401,
%U A158520 6800,6801,6802,6803,13604,13605,13606,27210,27211,27212,27213
%N A158520 Numbers n such that 2^n divided by the number of digits of 2^n is an integer.
%C A158520 Also n such that A000079(n)/A034887(n) is an integer.
%t A158520 ndnQ[n_]:=Module[{n2=2^n},Divisible[n2,IntegerLength[n2]]]; Select[Range[ 0,28000],ndnQ] (* _Harvey P. Dale_, Apr 16 2013 *)
%Y A158520 Cf. A000079, A034887
%K A158520 nonn,base,easy
%O A158520 1,3
%A A158520 _Ctibor O. Zizka_, Mar 20 2009
%E A158520 Extended by _R. J. Mathar_, Mar 26 2009