|
|
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
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,1
|
|
COMMENTS
|
|
|
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
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|