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A230787
T(n,k)=Number of nXk 0..3 arrays x(i,j) with each element horizontally, vertically, diagonally or antidiagonally next to at least one element with value (x(i,j)+1) mod 4, and upper left element zero
6
0, 0, 0, 0, 6, 0, 0, 86, 86, 0, 0, 820, 3332, 820, 0, 0, 8154, 117372, 117372, 8154, 0, 0, 82576, 4321988, 14875702, 4321988, 82576, 0, 0, 833986, 159055144, 1986882996, 1986882996, 159055144, 833986, 0, 0, 8417644, 5846988064, 265749521034
OFFSET
1,5
COMMENTS
Table starts
.0......0..........0..............0..................0......................0
.0......6.........86............820...............8154..................82576
.0.....86.......3332.........117372............4321988..............159055144
.0....820.....117372.......14875702.........1986882996...........265749521034
.0...8154....4321988.....1986882996.......974259190594........477873113683628
.0..82576..159055144...265749521034....477873113683628.....859151087187859602
.0.833986.5846988064.35493529463278.234034971045993736.1541982081513444808180
LINKS
FORMULA
Empirical for column k:
k=2: a(n) = 10*a(n-1) -3*a(n-2) +44*a(n-3) -40*a(n-4) +8*a(n-5) -192*a(n-6)
k=3: [order 20]
k=4: [order 67]
EXAMPLE
Some solutions for n=3 k=4
..0..2..1..0....0..1..1..3....0..1..1..1....0..1..2..0....0..2..1..1
..1..3..0..3....1..2..2..0....0..1..2..0....0..0..3..1....3..1..0..2
..2..1..2..1....1..2..3..1....1..2..3..1....2..3..0..2....1..2..0..3
CROSSREFS
Sequence in context: A229510 A358891 A358515 * A360424 A101109 A353224
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Oct 30 2013
STATUS
approved