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A210283
Number of 2 X 2 matrices with all elements in {0,1,...,n} and determinant n-1.
2
0, 10, 7, 20, 29, 59, 53, 126, 91, 185, 172, 274, 179, 481, 245, 456, 492, 672, 383, 948, 479, 1097, 870, 1030, 669, 1864, 980, 1376, 1354, 2017, 1029, 2768, 1201, 2508, 1984, 2260, 2090, 4124, 1667, 2790, 2682, 4538, 2009, 5068, 2243, 4519
OFFSET
0,2
COMMENTS
See A210000 for a guide to related sequences.
MATHEMATICA
a = 0; b = n; z1 = 45;
t[n_] := t[n] = Flatten[Table[w*z - x*y, {w, a, b}, {x, a, b}, {y, a, b}, {z, a, b}]]
c[n_, k_] := c[n, k] = Count[t[n], k]
Table[c[n, n - 1], {n, 0, z1}] (* A210283 *)
CROSSREFS
Cf. A210000.
Sequence in context: A068444 A210285 A190996 * A227473 A038309 A185264
KEYWORD
nonn
AUTHOR
Clark Kimberling, Mar 19 2012
STATUS
approved