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 A210282 #14 Nov 22 2016 02:38:33
%S A210282 1,3,12,21,43,45,102,75,161,156,234,163,433,221,424,460,608,359,876,
%T A210282 447,1049,830,942,637,1784,932,1304,1306,1905,997,2648,1137,2428,1920,
%U A210282 2164,2042,3980,1595,2694,2618,4378,1961,4900,2163,4423,4283
%N A210282 Number of 2 X 2 matrices with all elements in {0,1,...,n} and determinant n.
%C A210282 See A210000 for a guide to related sequences.
%H A210282 Chai Wah Wu, <a href="/A210282/b210282.txt">Table of n, a(n) for n = 0..2000</a>
%t A210282 a = 0; b = n; z1 = 45;
%t A210282 t[n_] := t[n] = Flatten[Table[w*z - x*y, {w, a, b}, {x, a, b}, {y, a, b}, {z, a, b}]]
%t A210282 c[n_, k_] := c[n, k] = Count[t[n], k]
%t A210282 Table[c[n, n], {n, 0, z1}] (* A210282 *)
%Y A210282 Cf. A210000.
%K A210282 nonn
%O A210282 0,2
%A A210282 _Clark Kimberling_, Mar 19 2012