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A197665 Number of n X n 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 4,0,1,0,1 for x=0,1,2,3,4 0
1, 9, 95, 5005, 709083, 311676959, 417293944115, 1717065757366333 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Every 0 is next to 0 4's, every 1 is next to 1 0's, every 2 is next to 2 1's, every 3 is next to 3 0's, every 4 is next to 4 1's

Diagonal of A197672

LINKS

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

EXAMPLE

Some solutions for n=4

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

..1..0..0..0....2..0..3..0....1..4..1..0....0..0..0..3....0..1..1..0

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

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

CROSSREFS

Sequence in context: A098450 A065456 A052389 * A064504 A090448 A264219

Adjacent sequences:  A197662 A197663 A197664 * A197666 A197667 A197668

KEYWORD

nonn

AUTHOR

R. H. Hardin Oct 17 2011

STATUS

approved

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Last modified March 30 09:13 EDT 2020. Contains 333125 sequences. (Running on oeis4.)