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A231080
T(n,k)=Number of nXk 0..2 arrays x(i,j) with each element horizontally, diagonally or antidiagonally next to at least one element with value (x(i,j)+1) mod 3 and at least one element with value (x(i,j)-1) mod 3, and upper left element zero
9
0, 0, 0, 0, 2, 0, 0, 14, 2, 0, 0, 40, 50, 16, 0, 0, 356, 136, 784, 34, 0, 0, 1840, 2820, 6400, 5098, 154, 0, 0, 10128, 38000, 523936, 71944, 54426, 432, 0, 0, 60808, 421920, 18937480, 18655220, 1866192, 441392, 1618, 0, 0, 337016, 6118120, 696453136
OFFSET
1,5
COMMENTS
Table starts
.0....0.......0.........0.............0..............0...............0
.0....2......14........40...........356...........1840...........10128
.0....2......50.......136..........2820..........38000..........421920
.0...16.....784......6400........523936.......18937480.......696453136
.0...34....5098.....71944......18655220.....1782634608....190102522528
.0..154...54426...1866192....1480839364...417868659864.131563996224512
.0..432..441392..32292680...79624748768.61990953794520
.0.1618.4164402.679262904.5187293040908
LINKS
FORMULA
Empirical for column k:
k=2: a(n) = 2*a(n-1) +6*a(n-2) -5*a(n-3)
k=3: [order 11]
k=4: [order 36]
Empirical for row n:
n=2: a(n) = 3*a(n-1) +12*a(n-2) +30*a(n-3) -64*a(n-4) +16*a(n-5)
n=3: [order 35]
EXAMPLE
Some solutions for n=3 k=4
..0..1..2..3....0..3..2..1....0..1..0..3....0..1..0..1....0..3..0..3
..2..3..0..3....2..1..0..1....0..3..2..3....2..3..2..3....0..1..2..3
..2..1..2..1....2..3..2..1....2..1..0..3....2..1..0..1....0..3..0..1
CROSSREFS
Column 2 is A230800
Sequence in context: A061848 A193294 A231049 * A231246 A216991 A191418
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Nov 03 2013
STATUS
approved