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 A167036 #14 Mar 15 2024 02:24:02
%S A167036 25,2500,7225,75625,250000,722500,2325625,7562500,25000000,72250000,
%T A167036 232562500,268140625,756250000,2500000000,7225000000,23256250000,
%U A167036 26814062500,68971890625,75625000000,250000000000,722500000000
%N A167036 Squares that remain squares prefixed with a 2.
%H A167036 Chai Wah Wu, <a href="/A167036/b167036.txt">Table of n, a(n) for n = 1..1000</a>
%e A167036 25 = 5^2 is a square and turns into the square 225 = 15^2 if a 2 is added in front.
%t A167036 Select[Range[850000]^2,IntegerQ[Sqrt[FromDigits[Join[{2}, IntegerDigits[ #]]]]]&] (* _Harvey P. Dale_, Jan 22 2013 *)
%K A167036 nonn,base
%O A167036 1,1
%A A167036 _Claudio Meller_, Oct 27 2009
%E A167036 Keyword:base added by _R. J. Mathar_, Oct 28 2009