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A187706 Number of 3X3 0..n arrays with each 2X2 subblock off diagonal and antidiagonal nonsingular and the array of 2X2 subblock determinants antisymmetric about the diagonal and antidiagonal 1
128, 1489, 8272, 31461, 93476, 235773, 524284, 1062857, 1999212, 3541677, 5967404, 9648841, 15048584, 22766353, 33534080, 48248321, 67983232, 94042589, 127929948, 171449249, 226655576, 295941137, 382036240, 488090685, 617595596, 774557293 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 2 of A187705

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..33

EXAMPLE

Some n=3 solutions for 3X3

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

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

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

CROSSREFS

Sequence in context: A070055 A247930 A200842 * A202961 A239540 A327772

Adjacent sequences:  A187703 A187704 A187705 * A187707 A187708 A187709

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 12 2011

STATUS

approved

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Last modified June 22 19:48 EDT 2021. Contains 345388 sequences. (Running on oeis4.)