A183762 Number of 2 X 2 nonsingular 0..n matrices with rows and columns in increasing order.

2, 16, 61, 163, 359, 687, 1206, 1966, 3040, 4498, 6435, 8917, 12077, 15993, 20788, 26588, 33542, 41744, 51397, 62595, 75543, 90407, 107382, 126582, 148292, 172670, 199931, 230277, 264005, 301225, 342332, 387452, 436902, 490948, 549841, 613831

Offset

1,1

Links

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

Example

Some solutions for n=2:
..0..1....0..1....1..2....0..1....1..2....1..2....0..2....0..2....0..2....0..1
..1..1....1..0....2..0....2..1....2..1....2..2....2..0....1..0....2..1....2..2

Crossrefs

Sequence in context: A208495 A207583 A152665 * A061608 A212899 A127276

Adjacent sequences: A183759 A183760 A183761 * A183763 A183764 A183765

Keyword

nonn

Author

R. H. Hardin, Jan 06 2011

Status

approved