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 A072471 #3 Dec 05 2013 19:55:20
%S A072471 0,25,144,256,900,1600,1764,3136,8100,14400,15876,28224,50176,129600,
%T A072471 142884,254016,302500,1742400,1920996,3415104,3956121,7033104,8767521,
%U A072471 15586704,27709696,64834704,94303521,167650704,298045696,617621904
%N A072471 Squares such that the sum of two neighboring term is also a square.
%C A072471 The sequence is unbounded.
%e A072471 144 is a term as 144 + 25 ( the previous term ) = 169 is a square and also 144 + 1225 ( the next term ) = 1369 = 37^2.
%t A072471 a[0] = 0; a[1] = 25; a[n_] := a[n] = (k = Sqrt[a[n - 1]] + 1; While[ !IntegerQ[ Sqrt[a[n - 1] + k^2]], k++ ]; k^2); Table[ a[n], {n, 0, 30}]
%Y A072471 Cf. A072470.
%K A072471 nonn
%O A072471 0,2
%A A072471 _Amarnath Murthy_, Jun 20 2002
%E A072471 Edited by _Robert G. Wilson v_, Jun 21 2002