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A204606
Number of (n+2)X9 0..2 arrays with every 3X3 subblock having three strictly increasing elements in a row horizontally, vertically or nw-to-se diagonally exactly one way
1
1240455298, 1982068849, 2572437376, 4518555426, 6656676736, 9620299328, 20253298532, 128896188864, 1430854315232, 8336227917170, 59924952387184, 645348966859136, 3709285229683898, 26509588554453184, 285311677590771520
OFFSET
1,1
COMMENTS
Column 7 of A204607
LINKS
FORMULA
Empirical: a(n) = 442*a(n-3) +43*a(n-6) for n>18
EXAMPLE
Some solutions for n=3
..1..0..1..0..2..2..0..0..1....0..1..0..0..0..2..2..0..1
..1..2..0..1..0..1..1..0..2....0..1..2..2..1..0..1..1..0
..0..1..2..2..1..0..2..1..1....1..0..1..2..2..1..0..2..1
..1..0..1..2..2..1..0..2..1....0..1..0..1..2..2..1..1..2
..1..0..0..1..2..2..0..1..2....0..1..2..0..1..2..2..1..1
CROSSREFS
Sequence in context: A176942 A154769 A187565 * A104966 A100004 A366068
KEYWORD
nonn
AUTHOR
R. H. Hardin Jan 17 2012
STATUS
approved