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A241108
T(n,k)=Number of nXk 0..2 arrays with no element equal to one or three horizontal or vertical neighbors, with new values 0..2 introduced in row major order
6
1, 1, 1, 2, 4, 2, 4, 11, 11, 4, 8, 36, 58, 36, 8, 16, 116, 294, 294, 116, 16, 32, 376, 1522, 2436, 1522, 376, 32, 64, 1216, 7846, 19814, 19814, 7846, 1216, 64, 128, 3936, 40418, 162776, 259388, 162776, 40418, 3936, 128, 256, 12736, 208374, 1333934, 3374086
OFFSET
1,4
COMMENTS
Table starts
...1.....1.......2.........4...........8.............16...............32
...1.....4......11........36.........116............376.............1216
...2....11......58.......294........1522...........7846............40418
...4....36.....294......2436.......19814.........162776..........1333934
...8...116....1522.....19814......259388........3374086.........44030862
..16...376....7846....162776.....3374086.......70145916.......1454236806
..32..1216...40418...1333934....44030862.....1454236806......48054344508
..64..3936..208374..10937316...574246744....30189380016....1586763763374
.128.12736.1074002..89651534..7489718098...626548445696...52415988665902
.256.41216.5535686.734979136.97685897406.13004327687556.1731396543937826
LINKS
FORMULA
Empirical for column k:
k=1: a(n) = 2*a(n-1) for n>2
k=2: a(n) = 2*a(n-1) +4*a(n-2) for n>4
k=3: a(n) = 3*a(n-1) +8*a(n-2) +16*a(n-3)
k=4: [order 10]
k=5: [order 26]
k=6: [order 76]
EXAMPLE
Some solutions for n=4 k=4
..0..1..1..2....0..1..1..2....0..1..2..0....0..1..0..2....0..1..2..0
..2..1..1..0....2..1..1..1....1..2..1..2....1..0..2..1....1..0..0..2
..1..0..2..1....0..2..1..1....2..1..2..0....2..1..1..0....2..0..0..0
..0..2..0..2....2..0..2..0....1..2..0..2....0..1..1..2....1..2..0..0
CROSSREFS
Column 1 is A000079(n-2)
Column 2 is A206687
Sequence in context: A282283 A288416 A240893 * A151706 A055372 A241078
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Apr 16 2014
STATUS
approved