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A263421
Number of nX3 arrays of permutations of 0..n*3-1 with each element moved a city block distance of 0 or 2.
1
2, 36, 1272, 26244, 532620, 11751184, 256052940, 5521233025, 119493228528, 2588597823744, 56036432705840, 1213019187980625, 26261187063569212, 568530651822400656, 12307989647701123268, 266454168798496644900
OFFSET
1,1
COMMENTS
Column 3 of A263424.
FORMULA
Empirical recurrence of order 64 (see link above)
EXAMPLE
Some solutions for n=4
..2..7..0....4..1..8....2..1..0....6..3..2....4..3..2....0..5..8....6..3..0
..3.10..1....9..2.11....5..4.11....1..0..7....1..0..5....3..2..1....1..2.11
..4..5..8....0..7..6....6..3..8....8..5.10....8..7.10....4.11.10....8..9.10
..9..6.11....3.10..5....7.10..9...11..4..9....9..6.11....9..6..7....7..4..5
CROSSREFS
Cf. A263424.
Sequence in context: A259467 A003092 A187535 * A046673 A245959 A174580
KEYWORD
nonn
AUTHOR
R. H. Hardin, Oct 17 2015
STATUS
approved