A226401 Number of nondecreasing -n..n vectors of length 4 whose dot product with some nonincreasing -n..n vector equals 4.

2, 48, 146, 448, 912, 1646, 2812, 4564, 6826, 9996, 14208, 19364, 26146, 34488, 44090, 56418, 71092, 87614, 107854, 131136, 156880, 187906, 223218, 261362, 305902, 356414, 410362, 472988, 542558, 615414, 700038, 792754, 890046, 1001146, 1120332

Offset

1,1

Comments

Row 4 of A226398.

Links

R. H. Hardin, Table of n, a(n) for n = 1..45

Example

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

Crossrefs

Sequence in context: A195876 A326778 A083251 * A226396 A341110 A075690

Adjacent sequences: A226398 A226399 A226400 * A226402 A226403 A226404

Keyword

nonn

Author

R. H. Hardin, Jun 06 2013

Status

approved