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A295207
Number of n X n 0..1 arrays with each 1 horizontally or vertically adjacent to 2 or 3 1's.
0
1, 2, 10, 147, 9536, 1245294, 444447937, 436106162865, 1123957773816109, 7694570450089060470, 140076394691747502547476
OFFSET
1,2
COMMENTS
Diagonal of A295213.
EXAMPLE
Some solutions for n=5
..1..1..1..0..0. .0..1..1..1..0. .0..0..0..1..1. .0..0..0..0..0
..1..0..1..1..0. .1..1..0..1..1. .1..1..0..1..1. .0..0..1..1..1
..1..1..0..1..1. .1..1..0..0..1. .1..1..1..1..0. .1..1..1..0..1
..0..1..0..0..1. .0..1..1..1..1. .1..0..0..1..0. .1..1..1..0..1
..0..1..1..1..1. .0..1..1..0..0. .1..1..1..1..0. .0..0..1..1..1
CROSSREFS
Cf. A295213.
Sequence in context: A152804 A188490 A317075 * A213457 A060595 A303440
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 17 2017
STATUS
approved