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 A185551 1/3 the number of n X n 0..2 arrays with every element equal to exactly one or two of its horizontal and vertical neighbors 0
 0, 5, 224, 58458, 64354744, 353403366772, 9079893278572272 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Diagonal of A185559 LINKS EXAMPLE Some solutions for 4X4 with a(1,1)=0 ..0..1..1..1....0..0..2..2....0..0..1..2....0..0..1..1....0..0..2..1 ..0..0..2..1....0..1..1..1....2..0..1..2....2..0..1..0....1..1..2..1 ..2..1..2..2....2..1..0..1....2..2..1..2....2..0..1..0....1..0..2..1 ..2..1..1..1....2..2..0..1....1..1..2..2....2..2..2..2....1..0..0..0 CROSSREFS Sequence in context: A112999 A337965 A225818 * A324098 A263430 A339311 Adjacent sequences:  A185548 A185549 A185550 * A185552 A185553 A185554 KEYWORD nonn AUTHOR R. H. Hardin Jan 31 2011 STATUS approved

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Last modified December 1 11:36 EST 2021. Contains 349429 sequences. (Running on oeis4.)