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A223452 Number of idempotent 3X3 -n..n matrices of rank 2 2
75, 399, 927, 1815, 2751, 4839, 6231, 8403, 10683, 14283, 16491, 21747, 24483, 29499, 35067, 40371, 43851, 52275, 56307, 65187, 73203, 81387, 86091, 98787, 105987, 115539, 124179, 136947, 143139, 163899, 170859, 182451, 195027, 207819, 220971 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 3 of A223450

LINKS

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

EXAMPLE

Some solutions for n=3

..2.-1..1....0..0..0...-1..0.-2...-2..2.-3....2..1..0....0.-2..2....1..1..0

..0..1..0....3..1..0...-1..1.-1...-3..3.-3...-2.-1..0....1..3.-2....0..0..0

.-2..2.-1...-3..0..1....1..0..2....0..0..1....1..1..1....1..2.-1....0..2..1

CROSSREFS

Sequence in context: A223078 A055561 A193252 * A015223 A129625 A133382

Adjacent sequences:  A223449 A223450 A223451 * A223453 A223454 A223455

KEYWORD

nonn

AUTHOR

R. H. Hardin Apr 09 2013

STATUS

approved

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Last modified December 11 07:41 EST 2019. Contains 329914 sequences. (Running on oeis4.)