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A205407 Number of (n+2)X(n+2) 0..2 arrays with every 3X3 subblock having three equal elements in a row horizontally, vertically or nw-to-se diagonally exactly two ways, and new values 0..2 introduced in row major order 1
468, 44596, 10331386, 2839359056, 2520131261396 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Diagonal of A205415

LINKS

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

EXAMPLE

Some solutions for n=3

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

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

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

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

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

CROSSREFS

Sequence in context: A282116 A281061 A270259 * A045305 A250238 A234125

Adjacent sequences:  A205404 A205405 A205406 * A205408 A205409 A205410

KEYWORD

nonn

AUTHOR

R. H. Hardin Jan 26 2012

STATUS

approved

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Last modified October 21 04:00 EDT 2021. Contains 348141 sequences. (Running on oeis4.)