A190096 Number of rhombuses on a (n+1)X8 grid

7, 32, 82, 164, 273, 412, 564, 736, 918, 1112, 1306, 1520, 1734, 1960, 2198, 2448, 2698, 2964, 3230, 3508, 3790, 4084, 4378, 4684, 4996, 5320, 5644, 5980, 6316, 6664, 7012, 7372, 7732, 8104, 8480, 8868, 9256, 9656, 10056, 10468, 10880, 11304, 11728, 12164

Offset

1,1

Comments

Column 7 of A190098

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>51

Example

Some solutions for n=3
..1..3....0..2....0..5....0..3....1..3....0..3....0..5....0..1....0..4....2..4
..1..5....1..1....1..3....1..5....2..0....0..6....1..4....1..3....0..7....2..5
..3..5....2..2....3..2....3..4....3..3....3..6....2..5....3..2....3..7....3..5
..3..3....1..3....2..4....2..2....2..6....3..3....1..6....2..0....3..4....3..4

Crossrefs

Sequence in context: A013656 A067982 A126562 * A254407 A219510 A164270

Adjacent sequences: A190093 A190094 A190095 * A190097 A190098 A190099

Keyword

nonn

Author

R. H. Hardin May 04 2011

Status

approved