|
|
A229375
|
|
Number of nX3 0..2 arrays avoiding 11 horizontally, 22 vertically and 00 diagonally or antidiagonally
|
|
1
|
|
|
22, 126, 956, 6730, 48490, 346598, 2486980, 17808604, 127696504, 914844004, 6558227280, 46993954326, 336844120550, 2413933454878, 17301596035866, 123994418056868, 888689321106698, 6369062557713410, 45647482408072212
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,1
|
|
COMMENTS
|
Column 3 of A229380
|
|
LINKS
|
R. H. Hardin, Table of n, a(n) for n = 1..210
|
|
FORMULA
|
Empirical: a(n) = 4*a(n-1) +50*a(n-2) -133*a(n-3) -653*a(n-4) +1214*a(n-5) +2281*a(n-6) -3420*a(n-7) -2248*a(n-8) +2704*a(n-9) +835*a(n-10) -481*a(n-11) -120*a(n-12)
|
|
EXAMPLE
|
Some solutions for n=4
..2..0..1....0..0..1....2..2..2....2..1..2....0..1..0....1..2..2....0..1..2
..1..0..2....1..2..1....0..0..1....1..2..0....1..2..1....0..0..1....1..2..0
..1..2..1....0..1..0....1..2..1....0..1..0....1..0..0....1..2..2....2..1..0
..0..1..0....0..2..0....1..0..2....2..2..1....2..1..2....0..0..0....0..1..2
|
|
CROSSREFS
|
Sequence in context: A209729 A252835 A220622 * A206418 A309923 A215626
Adjacent sequences: A229372 A229373 A229374 * A229376 A229377 A229378
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
R. H. Hardin Sep 21 2013
|
|
STATUS
|
approved
|
|
|
|