A189813 Number of right triangles on a (n+1)X9 grid

158, 550, 1236, 2250, 3596, 5250, 7224, 9496, 12044, 14860, 17948, 21266, 24852, 28634, 32604, 36780, 41168, 45716, 50440, 55324, 60384, 65612, 71000, 76532, 82240, 88116, 94136, 100300, 106624, 113100, 119744, 126532, 133472, 140560, 147792

Offset

1,1

Comments

Column 8 of A189814

Links

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

Formula

Empirical: a(n) = 72*n^2 + 2344*n - 23112 for n>63

Example

Some solutions for n=3
..2..8....2..2....0..6....0..6....3..0....1..3....0..2....0..8....3..5....3..8
..2..1....2..7....0..5....0..4....0..0....0..3....0..1....0..7....1..1....0..8
..3..8....3..2....2..6....1..6....3..8....1..7....1..2....3..8....1..6....3..7

Crossrefs

Sequence in context: A072555 A056088 A380474 * A270791 A180096 A250996

Adjacent sequences: A189810 A189811 A189812 * A189814 A189815 A189816

Keyword

nonn

Author

R. H. Hardin Apr 28 2011

Status

approved