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T(n,k)=Number of (n+1)X(k+1) 0..3 arrays with every 2X2 subblock having the sum of the squares of the edge differences equal to 6 (6 maximizes T(1,1))
9

%I #4 Dec 14 2013 16:21:21

%S 48,184,184,648,928,648,2440,4448,4448,2440,8712,23568,28544,23568,

%T 8712,32456,117744,216592,216592,117744,32456,116872,621904,1500800,

%U 2442208,1500800,621904,116872,432456,3145968,11482368,25036784,25036784

%N T(n,k)=Number of (n+1)X(k+1) 0..3 arrays with every 2X2 subblock having the sum of the squares of the edge differences equal to 6 (6 maximizes T(1,1))

%C Table starts

%C ......48.......184.........648..........2440............8712.............32456

%C .....184.......928........4448.........23568..........117744............621904

%C .....648......4448.......28544........216592.........1500800..........11482368

%C ....2440.....23568......216592.......2442208........25036784.........289389648

%C ....8712....117744.....1500800......25036784.......365293440........6336415296

%C ...32456....621904....11482368.....289389648......6336415296......169016684160

%C ..116872...3145968....81243904....3057995568.....95799636288.....3879764059776

%C ..432456..16510480...617735680...35239626640...1660462199232...103768584198400

%C .1565704..84078896..4416166400..377551693872..25500227965248..2432577744933760

%C .5768392.439062352.33345630720.4321333099024.438642994287168.64581965636210432

%H R. H. Hardin, <a href="/A233682/b233682.txt">Table of n, a(n) for n = 1..219</a>

%F Empirical for column k:

%F k=1: a(n) = a(n-1) +12*a(n-2) -4*a(n-3) -16*a(n-4)

%F k=2: [order 10]

%F k=3: [order 17]

%F k=4: [order 45]

%F k=5: [order 99]

%e Some solutions for n=3 k=4

%e ..0..2..0..2..0....1..1..1..2..1....0..1..3..1..0....0..0..0..2..3

%e ..0..1..0..1..0....0..2..0..2..3....0..2..2..2..2....1..2..1..2..1

%e ..2..1..2..1..2....0..1..1..2..1....0..1..0..1..3....0..2..3..2..0

%e ..2..3..3..1..3....2..2..3..2..3....0..2..2..2..2....0..1..3..1..1

%K nonn,tabl

%O 1,1

%A _R. H. Hardin_, Dec 14 2013