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 A210282 Number of 2 X 2 matrices with all elements in {0,1,...,n} and determinant n. 3

%I #14 Nov 22 2016 02:38:33

%S 1,3,12,21,43,45,102,75,161,156,234,163,433,221,424,460,608,359,876,

%T 447,1049,830,942,637,1784,932,1304,1306,1905,997,2648,1137,2428,1920,

%U 2164,2042,3980,1595,2694,2618,4378,1961,4900,2163,4423,4283

%N Number of 2 X 2 matrices with all elements in {0,1,...,n} and determinant n.

%C See A210000 for a guide to related sequences.

%H Chai Wah Wu, <a href="/A210282/b210282.txt">Table of n, a(n) for n = 0..2000</a>

%t a = 0; b = n; z1 = 45;

%t t[n_] := t[n] = Flatten[Table[w*z - x*y, {w, a, b}, {x, a, b}, {y, a, b}, {z, a, b}]]

%t c[n_, k_] := c[n, k] = Count[t[n], k]

%t Table[c[n, n], {n, 0, z1}] (* A210282 *)

%Y Cf. A210000.

%K nonn

%O 0,2

%A _Clark Kimberling_, Mar 19 2012

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Last modified July 13 17:31 EDT 2024. Contains 374284 sequences. (Running on oeis4.)