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A268116
Number of (n+1)Xn arrays containing n copies of 0..n+1-1 with every element equal to or 1 greater than any north or west neighbors modulo n and the upper left element equal to 0.
0
1, 2, 5, 15, 67, 457, 5628, 119908, 4350527
OFFSET
1,2
COMMENTS
Subdiagonal 1 of A268115.
EXAMPLE
Some solutions for n=6
..0..1..2..2..3..4....0..1..1..2..3..4....0..0..0..1..1..2....0..0..1..1..2..3
..1..2..3..3..4..5....1..2..2..3..4..5....0..1..1..1..2..3....0..1..1..2..3..4
..2..2..3..4..5..6....2..3..3..4..5..6....1..2..2..2..3..4....1..2..2..3..4..5
..2..3..4..5..6..0....2..3..4..5..6..6....2..3..3..3..4..5....1..2..3..4..5..6
..3..4..5..6..0..1....3..4..5..6..0..0....3..4..4..4..5..6....2..3..4..5..6..6
..4..5..6..0..0..1....4..5..6..0..0..1....4..5..5..5..6..0....3..4..5..5..6..0
..5..6..6..0..1..1....5..6..0..1..1..2....5..6..6..6..6..0....4..5..6..6..0..0
CROSSREFS
Cf. A268115.
Sequence in context: A166355 A031154 A270534 * A268123 A158079 A090091
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 26 2016
STATUS
approved