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A187407 Number of (n+1)X(n+1) 0..7 arrays with diagonal zero and the i,j-th 2X2 subblock sum equal to the j,i-th 2X2 subblock sum 0
64, 18152, 28371968, 268405348864, 16272446560731136, 6579936658033038000128 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 7 of A187408

LINKS

Table of n, a(n) for n=1..6.

EXAMPLE

Some solutions for 4X4

..0..4..0..7....0..0..4..0....0..4..0..5....0..0..4..7....0..4..0..4

..4..0..6..3....0..0..2..7....4..0..4..4....4..0..4..2....4..0..4..3

..0..6..0..0....0..6..0..6....2..2..0..5....4..0..0..3....0..4..0..4

..7..3..0..0....4..3..6..0....4..5..6..0....7..6..3..0....5..2..5..0

CROSSREFS

Sequence in context: A220853 A013781 A330482 * A271241 A283536 A089208

Adjacent sequences:  A187404 A187405 A187406 * A187408 A187409 A187410

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 09 2011

STATUS

approved

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Last modified September 20 17:16 EDT 2020. Contains 337265 sequences. (Running on oeis4.)