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A221311
T(n,k)=Number of idempotent n X n -k..k matrices of rank 1
1
1, 1, 10, 1, 26, 87, 1, 42, 447, 740, 1, 58, 999, 6820, 6285, 1, 74, 1935, 20708
OFFSET
1,3
COMMENTS
Table starts
....1....1.....1....1..1.1
...10...26....42...58.74
...87..447...999.1935
..740.6820.20708
.6285
EXAMPLE
Some solutions for n=3 k=4
..0.-3.-4....2.-1..1....4..4.-4....0..0..4...-2..3..4....1..2..2...-4.-4.-1
..0.-3.-4....0..0..0...-4.-4..4....0..0.-4...-2..3..4...-2.-4.-4....4..4..1
..0..3..4...-2..1.-1...-1.-1..1....0..0..1....0..0..0....2..4..4....4..4..1
CROSSREFS
Row 2 is A223451
Sequence in context: A243002 A050999 A223450 * A361949 A070246 A085044
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin Apr 10 2013
STATUS
approved