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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 (list; table; graph; refs; listen; history; text; internal format)
 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 LINKS 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 * A070246 A085044 A215268 Adjacent sequences:  A221308 A221309 A221310 * A221312 A221313 A221314 KEYWORD nonn,tabl AUTHOR R. H. Hardin Apr 10 2013 STATUS approved

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Last modified January 29 08:12 EST 2020. Contains 331337 sequences. (Running on oeis4.)