A226399 Number of nondecreasing -n..n vectors of length 2 whose dot product with some nonincreasing -n..n vector equals 2.

2, 12, 20, 32, 48, 64, 88, 112, 136, 168, 208, 232, 280, 328, 360, 408, 472, 520, 592, 640, 688, 768, 856, 904, 984, 1080, 1152, 1224, 1336, 1400, 1520, 1616, 1696, 1824, 1920, 1992, 2136, 2280, 2376, 2472, 2632, 2728, 2896, 3016, 3112, 3288, 3472, 3568, 3736

Offset

1,1

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Example

Some solutions for n=3:
  1  -2  -2  -3  -1   2  -2  -3  -1   0  -1   1   1  -3  -2  -2
  2   1  -1  -1   2   2  -2  -2   0   1  -1   1   3   2   0   3

Crossrefs

Row 2 of A226398.

Sequence in context: A023534 A286683 A326238 * A353399 A121859 A145622

Adjacent sequences: A226396 A226397 A226398 * A226400 A226401 A226402

Keyword

nonn

Author

R. H. Hardin, Jun 06 2013

Status

approved