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 A230669 Number of n X n 0..2 arrays x(i,j) with each element horizontally, diagonally or antidiagonally next to at least one element with value 2-x(i,j) 0
 0, 15, 1173, 730503, 4022141121, 169908632412447, 55314799986833459367, 140277459587738407279576815 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Diagonal of A230675 LINKS EXAMPLE Some solutions for n=3 ..2..2..0....1..1..1....1..2..0....0..1..0....1..1..0....1..1..2....2..0..1 ..0..0..0....0..2..2....0..1..0....1..2..1....2..2..0....1..0..0....1..1..1 ..2..2..2....2..0..2....0..2..0....0..1..1....0..0..0....0..2..0....2..0..2 CROSSREFS Sequence in context: A337677 A098210 A090213 * A027492 A001728 A326219 Adjacent sequences:  A230666 A230667 A230668 * A230670 A230671 A230672 KEYWORD nonn AUTHOR R. H. Hardin, Oct 27 2013 STATUS approved

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Last modified December 5 17:28 EST 2021. Contains 349557 sequences. (Running on oeis4.)