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A267630
Number of 4Xn arrays containing n copies of 0..4-1 with every element equal to or 1 greater than any west neighbor modulo 4 and the upper left element equal to 0.
1
6, 27, 208, 2386, 32208, 445970, 6039160, 80742586, 1086798652, 14898269746, 208430268352, 2964609577834, 42639468240764, 617605254789776, 8990677585470960, 131473208822453124, 1931423573382740480
OFFSET
1,1
COMMENTS
Row 4 of A267629.
LINKS
EXAMPLE
Some solutions for n=4
..0..1..1..2....0..0..0..0....0..0..1..1....0..1..2..2....0..0..0..1
..3..3..3..0....1..1..2..2....2..3..0..1....0..1..2..3....0..1..1..2
..0..0..1..2....1..1..2..2....2..2..3..3....3..0..1..2....1..2..3..3
..1..2..2..3....3..3..3..3....0..1..2..3....3..3..0..1....2..2..3..3
CROSSREFS
Cf. A267629.
Sequence in context: A223557 A289022 A060977 * A351737 A047778 A290802
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 18 2016
STATUS
approved