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A230840 T(n,k)=Number of nXk 0..3 arrays x(i,j) with each element horizontally, vertically 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, 2, 0, 0, 22, 22, 0, 0, 162, 656, 162, 0, 0, 1202, 16496, 16496, 1202, 0, 0, 8974, 416540, 1361842, 416540, 8974, 0, 0, 66990, 10550264, 114297392, 114297392, 10550264, 66990, 0, 0, 500018, 267165468, 9617769208, 32002769030, 9617769208 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,5

COMMENTS

Table starts

.0......0..........0..............0..................0......................0

.0......2.........22............162...............1202...................8974

.0.....22........656..........16496.............416540...............10550264

.0....162......16496........1361842..........114297392.............9617769208

.0...1202.....416540......114297392........32002769030..........8988055879558

.0...8974...10550264.....9617769208......8988055879558.......8428081775041778

.0..66990..267165468...809092017194...2523446670940914....7899599586975791528

.0.500018.6765343878.68064007019810.708459022763836116.7404104956669952823022

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..97

FORMULA

Empirical for column k:

k=2: a(n) = 8*a(n-1) -5*a(n-2) +8*a(n-3) -4*a(n-4)

k=3: [order 30] for n>31

EXAMPLE

Some solutions for n=3 k=4

..0..1..3..2....0..1..3..1....0..1..0..0....0..0..2..1....0..0..2..1

..0..2..0..3....3..2..0..2....3..2..2..1....1..0..3..2....1..2..3..2

..0..1..0..2....2..2..3..1....1..0..3..0....2..3..2..1....3..0..1..0

CROSSREFS

Sequence in context: A003784 A244143 A066294 * A209454 A287713 A287785

Adjacent sequences:  A230837 A230838 A230839 * A230841 A230842 A230843

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin, Oct 31 2013

STATUS

approved

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Last modified November 14 22:32 EST 2019. Contains 329134 sequences. (Running on oeis4.)