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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 (list; table; graph; refs; listen; history; text; internal format)
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

R. H. Hardin, Table of n, a(n) for n = 1..84

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: A019184 A019185 A229510 * A101109 A293526 A293568

Adjacent sequences:  A230784 A230785 A230786 * A230788 A230789 A230790

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin, Oct 30 2013

STATUS

approved

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Last modified November 23 17:10 EST 2020. Contains 338595 sequences. (Running on oeis4.)