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A223450 T(n,k)=Number of idempotent n X n -k..k matrices of rank n-1 2
1, 1, 10, 1, 26, 75, 1, 42, 399, 500, 1, 58, 927, 5220, 3125, 1, 74, 1815, 17380, 64285, 18750, 1, 106, 2751, 46884 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Table starts

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

....10....26....42....58...74.106

....75...399...927..1815.2751

...500..5220.17380.46884

..3125.64285

.18750

LINKS

Table of n, a(n) for n=1..25.

EXAMPLE

Some solutions for n=3 k=4

.-3..2.-1....1..0..1...-3..3..4...-1..0..2....1.-2..4....1..0..0...-3.-3..0

.-4..3.-1....0..1.-2...-4..4..4...-2..1..2....0..0..2....0..1..0....4..4..0

..4.-2..2....0..0..0....0..0..1...-1..0..2....0..0..1....3..3..0....0..0..1

CROSSREFS

Sequence in context: A013617 A243002 A050999 * A221311 A070246 A085044

Adjacent sequences:  A223447 A223448 A223449 * A223451 A223452 A223453

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin Apr 09 2013

STATUS

approved

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Last modified January 29 08:04 EST 2020. Contains 331337 sequences. (Running on oeis4.)