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A187403 Number of (n+1)X(n+1) 0..3 arrays with diagonal zero and the i,j-th 2X2 subblock sum equal to the j,i-th 2X2 subblock sum 0
16, 580, 59008, 18555136, 19210448896, 68711440384000, 884085911344119808, 42474221110291056295936 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A187408

LINKS

Table of n, a(n) for n=1..8.

EXAMPLE

Some solutions for 5X5

..0..2..0..0..0....0..2..0..2..2....0..2..0..2..2....0..0..0..2..2

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

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

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

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

CROSSREFS

Sequence in context: A089156 A210829 A222845 * A265638 A307943 A171210

Adjacent sequences:  A187400 A187401 A187402 * A187404 A187405 A187406

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 09 2011

STATUS

approved

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Last modified January 24 13:24 EST 2020. Contains 331193 sequences. (Running on oeis4.)