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 A303692 #23 Sep 08 2022 08:46:21
%S A303692 0,0,9,16,50,72,147,192,324,400,605,720,1014,1176,1575,1792,2312,2592,
%T A303692 3249,3600,4410,4840,5819,6336,7500,8112,9477,10192,11774,12600,14415,
%U A303692 15360,17424,18496,20825,22032,24642,25992,28899,30400,33620,35280,38829,40656
%N A303692 a(n) = n^2*(2*n - 3 - (-1)^n)/4.
%C A303692 Total area of all squares with side length n such that n = s + t and s < t where s and t are positive integers.
%H A303692 <a href="/index/Par#part">Index entries for sequences related to partitions</a>
%H A303692 <a href="/index/Rec#order_07">Index entries for linear recurrences with constant coefficients</a>, signature (1,3,-3,-3,3,1,-1).
%F A303692 a(n) = Sum_{i=1..floor((n-1)/2)} n^2.
%F A303692 a(n) = n^2 * floor((n-1)/2).
%F A303692 G.f.: x^2*(x^3 + 7*x^2 + 7*x + 9)/((x - 1)^4*(x + 1)^3).
%F A303692 Sum_{n>=3} 1/a(n) = 9/2 - 7*Pi^2/24 - 2*log(2). - _Vaclav Kotesovec_, May 02 2018
%t A303692 Table[n^2 (2 n - 3 - (-1)^n)/4, {n, 40}]
%t A303692 CoefficientList[ Series[(x^5 + 7x^4 + 7x^3 + 9x^2)/((x - 1)^4 (x + 1)^3), {x, 0, 43}], x] (* or *)
%t A303692 LinearRecurrence[{1, 3, -3, -3, 3, 1, -1}, {0, 0, 9, 16, 50, 72, 147}, 44] (* _Robert G. Wilson v_, Apr 28 2018 *)
%o A303692 (Magma) [n^2*(2*n-3-(-1)^n)/4: n in [1..50]]; // _Vincenzo Librandi_, Apr 30 2018
%o A303692 (PARI) a(n) = (n-1)\2*n^2; \\ _Altug Alkan_, Apr 30 2018
%Y A303692 Cf. A265645.
%K A303692 nonn,easy
%O A303692 1,3
%A A303692 _Wesley Ivan Hurt_, Apr 28 2018