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A266456
Number of 3Xn arrays containing n copies of 0..3-1 with no element 1 greater than its north neighbor modulo 3 and the upper left element equal to 0.
2
1, 5, 39, 357, 3471, 35003, 362265, 3821877, 40918431, 443234475, 4847042025, 53425329675, 592800026625, 6615155585925, 74183656771239, 835491101084757, 9445356930180735, 107140324945955483, 1218962144543118009
OFFSET
1,2
COMMENTS
Row 3 of A266455.
LINKS
EXAMPLE
Some solutions for n=4
..0..1..0..1....0..1..1..0....0..0..2..2....0..0..1..0....0..0..1..2
..2..0..0..1....2..1..1..2....2..0..1..1....2..2..1..2....2..0..1..2
..2..2..2..1....2..0..0..2....1..2..1..0....2..1..0..1....1..2..0..1
CROSSREFS
Cf. A266455.
Sequence in context: A213233 A115187 A378919 * A365765 A247772 A129763
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 29 2015
STATUS
approved