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 A127723 #6 Nov 04 2012 11:13:26
%S A127723 2,4,7,10,14,19,23,28,33,39,44,50,57,63,70,77,84,91,99,107,115,123,
%T A127723 131,140,148,157,166,175,184,194,204,213,223,233,244,254,265,275,286,
%U A127723 297,308,319,331,342,354,366,377,389,402,414,426,439,451,464,477,490,503
%N A127723 Floor of square root of sum of squares of the first n consecutive even numbers.
%t A127723 a = {}; k = 0; Do[k = k + x^2; AppendTo[a, Floor[Sqrt[k]]], {x, 2, 150, 2}]; a
%t A127723 Floor[Sqrt[#]]&/@Accumulate[Range[2,120,2]^2] (* _Harvey P. Dale_, Nov 04 2012 *)
%Y A127723 Cf. A127719, A127720, A127721, A127722.
%K A127723 nonn
%O A127723 1,1
%A A127723 _Artur Jasinski_, Jan 25 2007
%E A127723 Definition clarified by _Harvey P. Dale_, Nov 04 2012