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T(n,k)=Number of nXk 0..2 arrays with exactly floor(nXk/2) elements unequal to at least one horizontal, vertical or antidiagonal neighbor, with new values introduced in row major 0..2 order
7

%I #4 Feb 28 2013 07:16:36

%S 1,0,0,0,0,0,3,2,2,3,4,9,2,9,4,8,24,40,40,24,8,10,80,90,348,90,80,10,

%T 50,288,1336,2370,2370,1336,288,50,66,1038,3458,20606,17696,20606,

%U 3458,1038,66,216,3608,44516,212842,426362,426362,212842,44516,3608,216,280,12696

%N T(n,k)=Number of nXk 0..2 arrays with exactly floor(nXk/2) elements unequal to at least one horizontal, vertical or antidiagonal neighbor, with new values introduced in row major 0..2 order

%C Table starts

%C ....1......0........0...........3.............4...............8..............10

%C ....0......0........2...........9............24..............80.............288

%C ....0......2........2..........40............90............1336............3458

%C ....3......9.......40.........348..........2370...........20606..........212842

%C ....4.....24.......90........2370.........17696..........426362.........4030527

%C ....8.....80.....1336.......20606........426362.........9334575.......244592240

%C ...10....288.....3458......212842.......4030527.......244592240......5655834167

%C ...50...1038....44516.....2134959.....115311310......6696876400....433607685391

%C ...66...3608...126476....21085549....1138939624....189469189930..11560192314100

%C ..216..12696..1527344...211716164...33371066606...5486076619642.975276334243798

%C ..280..45024..4599422..2136631932..333504416113.160969581159830

%C .1120.160364.53131172.21522095442.9869885381863

%H R. H. Hardin, <a href="/A222673/b222673.txt">Table of n, a(n) for n = 1..144</a>

%e Some solutions for n=3 k=4

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

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

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

%Y Column 1 is A222395

%K nonn,tabl

%O 1,7

%A _R. H. Hardin_ Feb 28 2013