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 A036695 #24 Nov 23 2020 01:43:31
%S A036695 1,4,9,18,29,46,63,82,107,136,169,200,233,278,321,370,415,468,523,584,
%T A036695 649,708,781,850,921,1006,1087,1172,1255,1344,1441,1532,1637,1738,
%U A036695 1847,1962,2063,2184,2295,2428,2553,2672,2805,2938
%N A036695 a(n)=number of Gaussian integers z=a+bi satisfying |z|<=n, b>=0.
%C A036695 Number of ordered pairs of integers (x,y) with x^2 + y^2 <= n^2 and y >= 0. [_Reinhard Zumkeller_, Jan 23 2012]
%H A036695 Reinhard Zumkeller, <a href="/A036695/b036695.txt">Table of n, a(n) for n = 0..1000</a>
%H A036695 <a href="/index/Ga#gaussians">Index entries for Gaussian integers and primes</a>
%F A036695 Partial sums of A036696. - _Sean A. Irvine_, Nov 22 2020
%t A036695 a[n_] := (k = 0; Do[If[x^2 + y^2 <= n^2, k++], {x, -n, n}, {y, 0, n}]; k); Table[a[n], {n, 0, 100}] (* _Jean-François Alcover_, Oct 08 2016 *)
%o A036695 (Haskell)
%o A036695 a036695 n = length [(x,y) | x <- [-n..n], y <- [0..n], x^2 + y^2 <= n^2]
%o A036695 -- _Reinhard Zumkeller_, Jan 23 2012
%Y A036695 Cf. A000603, A000328, A036696.
%K A036695 nonn
%O A036695 0,2
%A A036695 _Clark Kimberling_