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A265922
Number of nX2 0..4 arrays with the absolute differences of each element with its with horizontal and antidiagonal neighbors unique.
1
25, 340, 4616, 62696, 851496, 11564952, 157071768, 2133318088, 28974227016, 393521606584, 5344722135352, 72590826767208, 985912408928360, 13390442524046040, 181866003973693912, 2470063509346243592
OFFSET
1,1
COMMENTS
Column 2 of A265928.
LINKS
FORMULA
Empirical: a(n) = 5*a(n-1) +110*a(n-2) +186*a(n-3) -1189*a(n-4) -2127*a(n-5) +4920*a(n-6) +5776*a(n-7) -9216*a(n-8)
EXAMPLE
Some solutions for n=4
..3..4....2..4....1..3....2..0....2..1....0..2....0..3....4..4....1..1....2..2
..1..0....3..3....2..4....1..1....3..0....1..4....4..0....2..2....2..0....3..1
..3..2....1..1....3..1....3..2....1..3....3..1....2..2....4..4....0..2....2..0
..4..1....2..4....0..0....4..0....4..0....0..4....4..3....3..1....1..1....0..1
CROSSREFS
Cf. A265928.
Sequence in context: A199657 A094730 A265930 * A136736 A119785 A067457
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 18 2015
STATUS
approved