|
|
A184378
|
|
1/12 the number of (n+2) X 3 0..2 arrays with each 3 X 3 subblock containing three of each value.
|
|
1
|
|
|
140, 545, 2174, 9113, 43295, 212747, 1096781, 6045233, 33958643, 194694395, 1141026791, 6726497945, 39885267065, 237890735825, 1421015749799, 8500910306963, 50929911923495, 305241246279617, 1830098075374121
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,1
|
|
COMMENTS
|
|
|
LINKS
|
|
|
FORMULA
|
Empirical: a(n) = 10*a(n-1)-27*a(n-2)+81*a(n-3)-630*a(n-4)+1701*a(n-5)-1620*a(n-6)+4860*a(n-7)-13122*a(n-8)+8748*a(n-9).
|
|
EXAMPLE
|
Some solutions with a(1,1)=0 for 4 X 3
..0..2..2....0..2..0....0..2..2....0..2..1....0..2..1....0..0..0....0..0..2
..1..1..2....2..1..1....0..1..1....0..1..2....1..0..0....2..2..2....1..2..2
..1..0..0....0..2..1....0..2..1....0..2..1....1..2..2....1..1..1....0..1..1
..2..2..0....0..2..0....2..2..0....2..0..1....2..0..1....0..0..0....2..0..0
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|