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A229380 T(n,k)=Number of nXk 0..2 arrays avoiding 11 horizontally, 22 vertically and 00 diagonally or antidiagonally 8
3, 8, 8, 22, 30, 22, 60, 126, 126, 60, 164, 518, 956, 518, 164, 448, 2138, 6730, 6730, 2138, 448, 1224, 8818, 48490, 78690, 48490, 8818, 1224, 3344, 36374, 346598, 956866, 956866, 346598, 36374, 3344, 9136, 150038, 2486980, 11441370, 20014278, 11441370 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Table starts

....3......8.......22.........60..........164............448.............1224

....8.....30......126........518.........2138...........8818............36374

...22....126......956.......6730........48490.........346598..........2486980

...60....518.....6730......78690.......956866.......11441370........138118032

..164...2138....48490.....956866.....20014278......407900408.......8454015792

..448...8818...346598...11441370....407900408....13999334726.....492938029980

.1224..36374..2486980..138118032...8454015792...492938029980...29757371834046

.3344.150038.17808604.1657198220.173331549156.17047266083040.1753378119210848

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..364

FORMULA

Empirical for column k:

k=1: a(n) = 2*a(n-1) +2*a(n-2)

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

k=3: [order 12]

k=4: [order 24] for n>25

k=5: [order 64] for n>65

EXAMPLE

Some solutions for n=3 k=4

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

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

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

CROSSREFS

Column 1 is A028859

Sequence in context: A209374 A101385 A161432 * A229372 A021261 A245263

Adjacent sequences:  A229377 A229378 A229379 * A229381 A229382 A229383

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin Sep 21 2013

STATUS

approved

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Last modified January 22 23:50 EST 2022. Contains 350504 sequences. (Running on oeis4.)