A210283 Number of 2 X 2 matrices with all elements in {0,1,...,n} and determinant n-1.

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.

Links

Chai Wah Wu, Table of n, a(n) for n = 0..3000

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

Adjacent sequences: A210280 A210281 A210282 * A210284 A210285 A210286

Keyword

nonn

Author

Clark Kimberling, Mar 19 2012

Status

approved