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A187623 Number of (n+1)X(n+1) 0..3 arrays with each 2X2 non-center subblock determinant nonzero and the array of 2X2 subblock determinants antisymmetric under 90 degree rotation 0
64, 2924, 390, 12278892, 4232368 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A187624

LINKS

Table of n, a(n) for n=1..5.

EXAMPLE

Some solutions for 4X4

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

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

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

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

CROSSREFS

Sequence in context: A283696 A283128 A295714 * A187631 A221831 A282397

Adjacent sequences:  A187620 A187621 A187622 * A187624 A187625 A187626

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 12 2011

STATUS

approved

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Last modified October 19 15:32 EDT 2021. Contains 348091 sequences. (Running on oeis4.)