A187697 - OEIS

A187697

Number of (n+1)X(n+1) 0..2 arrays with each 2X2 subblock determinant nonzero and the array of 2X2 subblock determinants symmetric under horizontal and vertical reflection

50, 8, 7954, 1548, 15128848, 454640, 231192094416

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OFFSET

1,1

COMMENTS

Column 2 of A187699

LINKS

Table of n, a(n) for n=1..7.

EXAMPLE

Some solutions for 4X4

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

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

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

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

CROSSREFS

Sequence in context: A036172 A242075 A187526 * A048178 A317619 A330848

Adjacent sequences: A187694 A187695 A187696 * A187698 A187699 A187700

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 12 2011

STATUS

approved