A221312 Number of idempotent 3X3 -n..n matrices of rank 1

87, 447, 999, 1935, 2871, 5079, 6399, 8679, 10971, 14667, 16755, 22323, 24795, 29979, 35643, 41019, 44259, 53139, 56763, 66123, 74043, 82203, 86595, 100035, 106755, 116403, 125091, 138243, 143787, 165627, 171555, 183867, 196347, 208971, 222267

Offset

1,1

Comments

Row 3 of A221311

Links

R. H. Hardin, Table of n, a(n) for n = 1..42

Example

Some solutions for n=3
.-1.-1.-1....0..0..0....0..0..0....0..3..3...-1.-2..0....0..2..2....3.-2..0
..3..3..3...-2..1..3...-1.-2.-3....0..2..2....1..2..0....0..2..2....3.-2..0
.-1.-1.-1....0..0..0....1..2..3....0.-1.-1....0..0..0....0.-1.-1....3.-2..0

Crossrefs

Sequence in context: A219723 A033631 A183724 * A098139 A359341 A297509

Adjacent sequences: A221309 A221310 A221311 * A221313 A221314 A221315

Keyword

nonn

Author

R. H. Hardin Apr 10 2013

Status

approved