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T(n,k)=Number of nXk 0..2 arrays avoiding 11 horizontally, 22 vertically and 00 diagonally or antidiagonally
8

%I #4 Sep 21 2013 07:07:47

%S 3,8,8,22,30,22,60,126,126,60,164,518,956,518,164,448,2138,6730,6730,

%T 2138,448,1224,8818,48490,78690,48490,8818,1224,3344,36374,346598,

%U 956866,956866,346598,36374,3344,9136,150038,2486980,11441370,20014278,11441370

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

%C Table starts

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

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

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

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

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

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

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

%C .3344.150038.17808604.1657198220.173331549156.17047266083040.1753378119210848

%H R. H. Hardin, <a href="/A229380/b229380.txt">Table of n, a(n) for n = 1..364</a>

%F Empirical for column k:

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

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

%F k=3: [order 12]

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

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

%e Some solutions for n=3 k=4

%e ..1..0..1..2....1..0..2..1....0..2..0..1....2..0..1..2....2..0..1..2

%e ..1..2..1..0....1..0..1..2....0..1..2..2....1..2..1..0....1..2..1..0

%e ..2..1..2..0....2..0..1..0....0..2..1..0....0..0..2..0....1..0..2..2

%Y Column 1 is A028859

%K nonn,tabl

%O 1,1

%A _R. H. Hardin_ Sep 21 2013