|
|
A267073
|
|
Number of 3Xn arrays containing n copies of 0..3-1 with no element 1 greater than its west or southwest neighbor modulo 3 and the upper left element equal to 0.
|
|
2
|
|
|
2, 2, 6, 31, 141, 550, 2046, 8149, 34902, 152001, 652150, 2761689, 11707811, 50123854, 216480177, 938377955, 4069585995, 17658916102, 76776575711, 334729181549, 1462999055814, 6405806909581, 28085236208039, 123289001886325
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,1
|
|
COMMENTS
|
|
|
LINKS
|
|
|
EXAMPLE
|
Some solutions for n=4
..0..0..2..1....0..2..2..1....0..0..2..1....0..0..2..1....0..2..1..1
..1..0..2..1....0..2..1..0....0..2..1..1....0..2..2..1....2..2..1..0
..0..2..2..1....2..1..1..0....0..2..2..1....0..2..1..1....2..1..0..0
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|