%I
%S 154,670,670,2900,2498,2900,12578,9328,9328,12578,54530,35354,30312,
%T 35354,54530,236496,135254,101464,101464,135254,236496,1025770,523532,
%U 345280,304746,345280,523532,1025770,4449942,2047890,1201872,937034
%N T(n,k)=Number of (n+1)X(k+1) 0..6 arrays with every 2X2 subblock having its diagonal sum differing from its antidiagonal sum by 4, with no adjacent elements equal (constant stress tilted 1X1 tilings)
%C Table starts
%C ......154.......670......2900.....12578.....54530.....236496....1025770
%C ......670......2498......9328.....35354....135254.....523532....2047890
%C .....2900......9328.....30312....101464....345280....1201872....4256548
%C ....12578.....35354....101464....304746....937034....2978124....9680994
%C ....54530....135254....345280....937034...2613410....7614452...22754394
%C ...236496....523532...1201872...2978124...7614452...20552136...57035088
%C ..1025770...2047890...4256548...9680994..22754394...57035088..147069470
%C ..4449942...8097130..15381300..32349918..70442910..165182704..398750942
%C .19307284..32339728..56526280.110399304.223243440..490588960.1109052788
%C .83782730.130423938.211590104.385970050.729220586.1509762708.3214407394
%H R. H. Hardin, <a href="/A235107/b235107.txt">Table of n, a(n) for n = 1..178</a>
%F Empirical for column k:
%F k=1: a(n) = 7*a(n-1) -2*a(n-2) -47*a(n-3) +3*a(n-4) +84*a(n-5) +36*a(n-6)
%F k=2: [order 19]
%F k=3: [order 62]
%e Some solutions for n=3 k=4
%e ..3..1..0..1..3....4..6..3..2..4....1..4..5..2..0....1..6..4..1..3
%e ..6..0..3..0..6....6..4..5..0..6....6..5..2..3..5....0..1..3..4..2
%e ..3..1..0..1..3....3..5..2..1..3....5..0..1..6..4....1..6..4..1..3
%e ..4..6..1..6..4....4..2..3..6..4....6..5..2..3..5....0..1..3..4..2
%K nonn,tabl
%O 1,1
%A _R. H. Hardin_, Jan 03 2014
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