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 A208020 Number of n X 5 nonnegative integer arrays with new values 0 upwards introduced in row major order and no element equal to any horizontal, vertical, diagonal or antidiagonal neighbor (colorings ignoring permutations of colors). 2
 15, 1657, 5252041, 80318704605, 3662498214110836, 387950830575476495043, 81811898713607232898679186, 30915192640251267259536636853106, 19388812191991157504565482403825817325, 19036318336696557481934278608884237849314405 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Andrew Howroyd, Table of n, a(n) for n = 1..50 EXAMPLE Some solutions for n=4 ..0..1..0..1..0....0..1..2..0..1....0..1..0..1..0....0..1..0..1..0 ..2..3..2..3..4....2..3..4..3..2....2..3..2..3..2....2..3..2..3..2 ..0..4..1..0..1....1..0..1..0..1....0..1..0..1..0....0..1..4..0..1 ..2..3..2..3..2....2..3..2..3..2....2..3..2..3..2....2..3..2..3..2 CROSSREFS Column 5 of A208021. Sequence in context: A281801 A208000 A182925 * A205423 A263600 A208860 Adjacent sequences: A208017 A208018 A208019 * A208021 A208022 A208023 KEYWORD nonn AUTHOR R. H. Hardin, Feb 22 2012 EXTENSIONS Terms a(6) and beyond from Andrew Howroyd, Jun 25 2017 STATUS approved

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Last modified December 9 18:33 EST 2023. Contains 367693 sequences. (Running on oeis4.)