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 A051206 #9 May 14 2017 03:00:47
%S A051206 0,3,5,8,9,12,15,17,20,21,24,32,33,35,36,45,48,57,60,63,65,68,77,80,
%T A051206 84,96,99,105,117,120,128,129,132,140,143,144,153,161,165,168,180,185,
%U A051206 192,195,201,209,221,224,225,228,240,252,255,257,260,272,273,285,288,297
%N A051206 Numbers of the form x^2-4^y >= 0.
%t A051206 max = 300; Clear[f]; f[m_] := f[m] = Select[Table[x^2 - 4^y, {y, 0, m}, {x, Floor[4^(y/2)], Ceiling[Sqrt[4^y + max]]}] // Flatten // Union, 0 <= # <= max &]; f[1]; f[m = 2]; While[f[m] != f[m - 1], m++]; Print["m = ", m]; A051206 = f[m] (* _Jean-François Alcover_, May 14 2017 *)
%K A051206 nonn
%O A051206 1,2
%A A051206 _David W. Wilson_