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A187720 Number of (n+1)X(n+1) binary arrays with no 2X2 subblock commuting with any of its horizontal and vertical 2X2 subblock neighbors 0
16, 174, 3698, 161571, 13555195, 2287444987, 755272970945, 491415809239410, 627561470269866658, 1574769693877593164368 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Diagonal of A187729

LINKS

Table of n, a(n) for n=1..10.

EXAMPLE

Some solutions for 3X3

..0..0..1....1..0..1....1..0..1....0..1..1....1..1..1....1..0..0....1..1..1

..1..1..1....1..1..0....1..1..0....0..1..0....0..0..1....1..0..1....0..1..0

..0..1..0....1..1..0....1..1..1....1..1..1....1..0..1....1..1..0....1..0..0

CROSSREFS

Sequence in context: A021374 A253343 A215687 * A017931 A021129 A268869

Adjacent sequences:  A187717 A187718 A187719 * A187721 A187722 A187723

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 13 2011

STATUS

approved

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Last modified May 11 11:54 EDT 2021. Contains 343791 sequences. (Running on oeis4.)