A190095 Number of rhombuses on a (n+1)X7 grid.

6, 26, 66, 130, 212, 312, 412, 527, 650, 782, 914, 1059, 1204, 1358, 1520, 1691, 1862, 2044, 2226, 2417, 2608, 2808, 3008, 3217, 3430, 3652, 3874, 4105, 4336, 4576, 4816, 5065, 5314, 5572, 5830, 6097, 6364, 6640, 6916, 7201, 7486, 7780, 8074, 8377, 8680

Offset: 1

Author

R. H. Hardin May 04 2011

Keywords

• nonn

Comments

Column 6 of A190098

Examples

			Some solutions for n=3
..0..1....0..6....0..4....0..2....1..5....0..4....0..2....0..1....0..4....1..1
..1..0....1..4....1..2....0..5....1..6....0..5....0..3....1..3....1..2....1..3
..2..1....3..3....2..4....3..5....2..6....1..5....1..3....3..2....3..1....3..3
..1..2....2..5....1..6....3..2....2..5....1..4....1..2....2..0....2..3....3..1
		

Links

• R. H. Hardin, Table of n, a(n) for n = 1..200

Formula

Empirical: a(n) = 2*a(n-1) -2*a(n-3) +a(n-4) for n>27