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A198178 Number of n X n 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 0,2,1,0,0 for x=0,1,2,3,4 0
1, 4, 9, 59, 2033, 51688, 4522496, 559601114, 174674654015 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

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

Diagonal of A198185

LINKS

Table of n, a(n) for n=1..9.

EXAMPLE

Some solutions for n=4

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

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

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

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

CROSSREFS

Sequence in context: A197859 A197997 A309444 * A013571 A002942 A028908

Adjacent sequences:  A198175 A198176 A198177 * A198179 A198180 A198181

KEYWORD

nonn

AUTHOR

R. H. Hardin Oct 21 2011

STATUS

approved

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Last modified May 9 20:59 EDT 2021. Contains 343746 sequences. (Running on oeis4.)