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 A045787 #14 Sep 04 2021 15:29:42
%S A045787 4,49,400,441,484,4096,4225,4356,4489,4624,4761,4900,40000,40401,
%T A045787 40804,41209,41616,42025,42436,42849,43264,43681,44100,44521,44944,
%U A045787 45369,45796,46225,46656,47089,47524,47961,48400,48841,49284,49729,400689
%N A045787 Squares with initial digit '4'.
%F A045787 a(n) = A045858(n)^2. - _Michel Marcus_, Sep 04 2021
%t A045787 Flatten[Table[Range[Ceiling[Sqrt[4 10^n]],Floor[Sqrt[5 10^n]]]^2, {n,5}]] (* _Harvey P. Dale_, Jun 15 2011 *)
%Y A045787 Cf. A045858.
%Y A045787 Cf. A045784, A045785, A045786, A045788, A045789, A045791, A045792, A045793.
%K A045787 nonn,base
%O A045787 1,1
%A A045787 _Jeff Burch_