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 A162401 #16 Jun 16 2018 19:52:04
%S A162401 1,1,1,2,1,1,1,2,3,1,1,2,1,1,1,4,2,3,3,2,1,1,1,2,5,1,1,2,1,1,1,4,4,2,
%T A162401 2,6,3,3,3,2,3,1,1,2,1,1,1,4,7,5,5,2,1,1,1,2,5,1,1,2,1,1,1,8,4,4,4,2,
%U A162401 2,2,2,6,6,3,3,3,3,3,3,4,9,3,3,2,1,1,1,2,5,1,1,2,1,1,1,4,4,7,7
%N A162401 a(n) is the largest integer whose square, when represented in binary, is a substring within the binary representation of n.
%C A162401 A162400(n) = A162401(n)^2.
%H A162401 Alois P. Heinz, <a href="/A162401/b162401.txt">Table of n, a(n) for n = 1..16384</a> (first 10000 terms from Robert G. Wilson v)
%t A162401 f[n_] := Block[{k = Floor@ Sqrt@ n, s = ToString@ FromDigits@ IntegerDigits[n, 2]}, While[ StringPosition[s, ToString@ FromDigits@ IntegerDigits[k^2, 2]] == {}, k-- ]; k]; Array[f, 105] (* _Robert G. Wilson v_, Jul 16 2009 *)
%Y A162401 Cf. A162400.
%K A162401 base,nonn,look
%O A162401 1,4
%A A162401 _Leroy Quet_, Jul 02 2009
%E A162401 a(16) correction and more terms from _Robert G. Wilson v_, Jul 16 2009