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 A220270 #23 Aug 31 2014 07:48:07
%S A220270 2,43,537,5866,61466,630509,6410996,64836667,653704646,6578501544,
%T A220270 66115091613,663868597795,6661437722643,66808391053328,
%U A220270 669760217536267,6712237657325964,67251395887426191
%N A220270 Number of biased numbers (A101550) less than 10^n.
%H A220270 G. Everest, S. Stevens, D. Tamsett and T. Ward, <a href="http://arxiv.org/abs/math/0412079">Primes Generated by Recurrence Sequences</a>, arXiv:math/0412079 [math.NT], 2004-2006.
%F A220270 a(n) ~ 10^n*log(2) as n -> infinity.
%t A220270 Accumulate@Table[Length@Select[Range[10^(n - 1), 10^n - 1], FactorInteger[#][[-1, 1]] > 2*Sqrt[#] &], {n, 5}] (* or *)
%t A220270 lst = {}; s = -2; Do[Do[If[PrimeQ[i] || FactorInteger[i][[-1, 1]] > 2*Sqrt[i], s++], {i, 10^(n - 1), 10^n - 1}]; AppendTo[lst, s], {n, 5}]; lst
%Y A220270 Cf. A101550, A002162.
%K A220270 more,nonn
%O A220270 1,1
%A A220270 _Arkadiusz Wesolowski_, Dec 11 2012
%E A220270 a(9)-a(11) from _Donovan Johnson_, Dec 12 2012
%E A220270 a(12)-a(17) from _Hiroaki Yamanouchi_, Aug 31 2014