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 A231040 Number of 4Xn 0..2 arrays x(i,j) with each element horizontally, diagonally or antidiagonally next to at least one element with value (x(i,j)+1) mod 3 and at least one element with value (x(i,j)-1) mod 3, and upper left element zero 1
 0, 0, 32, 1344, 17984, 677204, 18856728, 564645420, 16234948496, 475975504692, 13857021589642, 404691502166966, 11799362329503764, 344308929571301874, 10043260926278906802, 293007140636817319366, 8547634832665972057722 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS Row 4 of A231037 LINKS R. H. Hardin, Table of n, a(n) for n = 1..210 EXAMPLE Some solutions for n=3 ..0..1..0....0..2..0....0..2..0....0..2..0....0..1..0....0..1..0....0..2..0 ..1..2..2....2..1..1....1..1..2....2..1..1....2..2..2....2..2..1....0..1..1 ..0..0..0....0..0..1....0..0..0....0..0..2....1..0..0....0..0..1....0..0..2 ..2..1..2....1..2..1....1..2..1....1..2..1....2..1..2....2..1..2....1..2..1 CROSSREFS Sequence in context: A275036 A274732 A241800 * A254152 A160447 A302263 Adjacent sequences:  A231037 A231038 A231039 * A231041 A231042 A231043 KEYWORD nonn AUTHOR R. H. Hardin, Nov 03 2013 STATUS approved

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Last modified December 8 17:01 EST 2021. Contains 349596 sequences. (Running on oeis4.)