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A224118 T(n,k)=Number of idempotent n X n 0..k matrices of rank n-2 4
0, 0, 1, 0, 1, 27, 0, 1, 69, 282, 0, 1, 123, 1434, 2050, 0, 1, 195, 4182, 20810, 12405, 0, 1, 273, 9762, 103050, 260235, 67557, 0, 1, 375, 19110, 368130, 2273505, 3037167, 344708, 0, 1, 477, 34602, 1042030, 12775065, 47922021, 34229076, 1686132, 0, 1, 603 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,6

COMMENTS

Table starts

.......0........0........0.........0........0.......0.....0...0.0.0

.......1........1........1.........1........1.......1.....1...1.1

......27.......69......123.......195......273.....375...477.603

.....282.....1434.....4182......9762....19110...34602.56982

....2050....20810...103050....368130..1042030.2563150

...12405...260235..2273505..12775065.52968495

...67557..3037167.47922021.427616679

..344708.34229076

.1686132

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..52

EXAMPLE

Some solutions for n=3 k=4

..1..0..0....1..3..0....1..3..0....0..3..3....0..0..0....0..1..0....0..0..1

..1..0..0....0..0..0....0..0..0....0..1..1....0..0..1....0..1..0....0..0..3

..3..0..0....1..3..0....0..0..0....0..0..0....0..0..1....0..0..0....0..0..1

CROSSREFS

Row 3 is A224525

Row 4 is A224115

Sequence in context: A005084 A050454 A277042 * A178737 A005067 A163574

Adjacent sequences:  A224115 A224116 A224117 * A224119 A224120 A224121

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin Apr 09 2013

STATUS

approved

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Last modified July 11 01:51 EDT 2020. Contains 335600 sequences. (Running on oeis4.)