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T(n,k)=Number of nXk 0..3 arrays with every element plus 1 mod 4 equal to some element at offset (-1,0) (-1,1) (0,-1) (0,1) or (1,0), with upper left element zero.
5

%I #4 Nov 12 2016 06:56:01

%S 0,0,0,0,2,0,0,10,10,0,0,58,164,58,0,0,334,2996,2996,334,0,0,1910,

%T 52310,165408,52310,1910,0,0,10910,911096,8817738,8817738,911096,

%U 10910,0,0,62314,15854438,469476315,1432970150,469476315,15854438,62314,0,0,355898

%N T(n,k)=Number of nXk 0..3 arrays with every element plus 1 mod 4 equal to some element at offset (-1,0) (-1,1) (0,-1) (0,1) or (1,0), with upper left element zero.

%C Table starts

%C .0.......0...........0..............0................0.................0

%C .0.......2..........10.............58..............334..............1910

%C .0......10.........164...........2996............52310............911096

%C .0......58........2996.........165408..........8817738.........469476315

%C .0.....334.......52310........8817738.......1432970150......232444783982

%C .0....1910......911096......469476315.....232444783982...114893826834782

%C .0...10910....15854438....24968293789...37664268929810.56727696580816184

%C .0...62314...275796494..1327640457829.6101731863309598

%C .0..355898..4797380865.70590643428412

%C .0.2032630.83447002829

%H R. H. Hardin, <a href="/A278099/b278099.txt">Table of n, a(n) for n = 1..83</a>

%F Empirical for column k:

%F k=2: a(n) = 6*a(n-1) -a(n-2) -3*a(n-3) -3*a(n-4) -6*a(n-5) +2*a(n-7)

%F k=3: [order 48] for n>49

%e Some solutions for n=4 k=4

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

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

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

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

%K nonn,tabl

%O 1,5

%A _R. H. Hardin_, Nov 12 2016