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A278280
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T(n,k) = Number of n X k 0..1 arrays with every element both equal and not equal to some elements at offset (-1,-1) (-1,0) (-1,1) (0,-1) (0,1) or (1,0), with upper left element zero.
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14
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0, 0, 0, 0, 2, 0, 0, 4, 5, 0, 0, 13, 25, 16, 0, 0, 36, 122, 136, 49, 0, 0, 109, 661, 1461, 839, 153, 0, 0, 317, 3723, 15728, 16842, 5013, 476, 0, 0, 938, 20736, 172091, 350649, 196726, 30370, 1483, 0, 0, 2754, 115446, 1870365, 7466627, 7974561, 2293193
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OFFSET
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1,5
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COMMENTS
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Table starts
.0.....0.......0..........0.............0................0..................0
.0.....2.......4.........13............36..............109................317
.0.....5......25........122...........661.............3723..............20736
.0....16.....136.......1461.........15728...........172091............1870365
.0....49.....839......16842........350649..........7466627..........157609938
.0...153....5013.....196726.......7974561........329985827........13538466880
.0...476...30370....2293193.....180592726......14526103064......1158266740087
.0..1483..183403...26748095....4093629985.....640011857446.....99182079495633
.0..4619.1108525..311952675...92770708201...28192246592564...8491049196878995
.0.14388.6699034.3638315600.2102508396678.1241921389868057.726961954823301592
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LINKS
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FORMULA
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Empirical for column k:
k=2: a(n) = 3*a(n-1) +a(n-2) -2*a(n-3) for n>4.
k=3: a(n) = 6*a(n-1) +3*a(n-2) -17*a(n-3) +19*a(n-5) -16*a(n-6) +8*a(n-7) for n>9.
k=4: [order 17] for n>19.
k=5: [order 44] for n>46.
k=6: [order 98] for n>101.
Empirical for row n:
n=2: a(n) = 2*a(n-1) +3*a(n-2) -a(n-3) +a(n-4).
n=3: [order 16].
n=4: [order 40].
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EXAMPLE
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Some solutions for n=4, k=4
..0..1..1..0. .0..1..0..1. .0..1..1..1. .0..1..0..1. .0..1..1..0
..0..0..1..0. .0..1..0..1. .0..0..0..0. .0..1..0..1. .0..0..1..0
..0..1..1..1. .0..1..0..1. .1..1..1..0. .0..0..0..1. .0..1..1..0
..0..0..0..0. .1..0..1..1. .1..0..0..1. .0..1..1..1. .1..0..0..1
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CROSSREFS
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KEYWORD
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AUTHOR
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STATUS
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approved
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