A190097 Number of rhombuses on a (n+1)X9 grid.
8, 39, 100, 204, 344, 527, 736, 984, 1244, 1520, 1796, 2104, 2412, 2736, 3076, 3438, 3800, 4184, 4568, 4968, 5376, 5800, 6224, 6668, 7120, 7588, 8056, 8540, 9024, 9524, 10024, 10542, 11060, 11594, 12136, 12694, 13252, 13826, 14400, 14990, 15580, 16186
Offset: 1
Keywords
Examples
Some solutions for n=3 ..0..3....1..1....1..5....0..5....0..5....1..0....0..5....0..4....2..4....1..3 ..0..5....1..2....2..2....0..7....1..7....1..1....1..4....1..2....2..5....1..5 ..2..5....2..2....3..5....2..7....3..6....2..1....2..5....2..4....3..5....3..5 ..2..3....2..1....2..8....2..5....2..4....2..0....1..6....1..6....3..4....3..3
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
Comments