A229380 T(n,k)=Number of nXk 0..2 arrays avoiding 11 horizontally, 22 vertically and 00 diagonally or antidiagonally

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

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 A357406 A021261

Adjacent sequences: A229377 A229378 A229379 * A229381 A229382 A229383

Keyword

nonn,tabl

Author

R. H. Hardin Sep 21 2013

Status

approved