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 A000592 M2324 N0919 #34 Sep 02 2023 04:37:22
%S A000592 1,3,4,6,8,9,11,13,15,17,19,20,22,26,28,30,31,33,35,37,39,41,43,45,48,
%T A000592 50,52,54,56,58,62,64,65,67,69,71,73,75,79,81,83,85,86,90,92,94,96,98,
%U A000592 100,102,104,106,108,112,113,117,119,121,123,127,129,131,133,135,137
%N A000592 Number of nonnegative solutions of x^2 + y^2 = z in first n shells.
%C A000592 Cumulative totals of nonzero values in (or distinct values in cumulative totals of) A000925. - _Franklin T. Adams-Watters_, Jun 21 2006
%D A000592 Hansraj Gupta, A table of values of N_2(t), Res. Bull. East Panjab Univ. 1952, (1952). no. 20, 13-93.
%D A000592 N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
%D A000592 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%H A000592 T. D. Noe, <a href="/A000592/b000592.txt">Table of n, a(n) for n = 0..2749</a>
%F A000592 N_2(t) = Sum_{j <= t} n_2(j) where n_2(j) is the number of nonnegative solutions (x,y) of x^2 + y^2 = j, the solution (x,y) being considered as different from (y,x) in case x != y.
%t A000592 nn = 200; t = CoefficientList[Series[Sum[x^k^2, {k, 0, Sqrt[nn]}]^2, {x, 0, nn}], x]; Union[Accumulate[t]] (* _Jean-François Alcover_, Jul 20 2011, after _T. D. Noe_ *)
%Y A000592 Cf. A000925.
%K A000592 nonn,nice,easy
%O A000592 0,2
%A A000592 _N. J. A. Sloane_
%E A000592 More terms from _Franklin T. Adams-Watters_, Jun 21 2006