A209988 Number of 2 X 2 matrices having all elements in {-n,...n} and determinant 4.

0, 0, 52, 116, 364, 492, 684, 876, 1260, 1452, 1836, 2156, 2668, 3052, 3628, 3884, 4652, 5164, 5740, 6316, 7340, 7724, 8684, 9388, 10156, 10796, 11948, 12524, 14060, 14956, 15724, 16684, 18220, 18860, 20396, 21164, 22700, 23852, 25580

Offset

0,3

Comments

See A210000 for a guide to related sequences.

Links

Chai Wah Wu, Table of n, a(n) for n = 0..10000

Mathematica

(See the Mathematica section at A209981.)

Crossrefs

Cf. A210000.

Sequence in context: A252336 A044239 A044620 * A326912 A327147 A346898

Adjacent sequences: A209985 A209986 A209987 * A209989 A209990 A209991

Keyword

nonn

Author

Clark Kimberling, Mar 17 2012

Status

approved