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A283950
T(n,k)=Number of nXk 0..1 arrays with no 1 equal to more than three of its horizontal, diagonal and antidiagonal neighbors, with the exception of exactly one element.
12
0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 16, 87, 0, 0, 0, 84, 906, 900, 0, 0, 0, 408, 7988, 16648, 8184, 0, 0, 0, 1926, 69468, 264482, 283208, 71486, 0, 0, 0, 8776, 575456, 4242700, 8244557, 4510608, 597042, 0, 0, 0, 38912, 4604744, 64614384, 241796070, 242330064
OFFSET
1,8
COMMENTS
Table starts
.0.0......0........0..........0............0..............0................0
.0.0......2.......16.........84..........408...........1926.............8776
.0.0.....87......906.......7988........69468.........575456..........4604744
.0.0....900....16648.....264482......4242700.......64614384........948567440
.0.0...8184...283208....8244557....241796070.....6763514843.....182198176994
.0.0..71486..4510608..242330064..13010689912...667015216686...32960788748780
.0.0.597042.68693470.6816984648.669777003928.62944601744067.5709831013093658
LINKS
FORMULA
Empirical for column k:
k=1: a(n) = a(n-1)
k=2: a(n) = a(n-1)
k=3: [order 16]
k=4: [order 34]
k=5: [order 90]
Empirical for row n:
n=1: a(n) = a(n-1)
n=2: [order 8]
n=3: [order 28]
n=4: [order 56]
EXAMPLE
Some solutions for n=4 k=4
..1..0..1..0. .0..1..1..1. .1..0..1..0. .1..1..0..1. .0..1..0..0
..1..1..0..1. .0..1..1..0. .0..0..0..1. .1..0..1..1. .0..0..0..1
..1..1..0..0. .1..1..0..0. .1..1..1..0. .0..1..0..0. .1..1..1..1
..1..1..0..0. .0..0..0..1. .1..1..0..1. .0..0..1..1. .0..1..0..0
CROSSREFS
Sequence in context: A348029 A224074 A136615 * A342376 A277443 A209401
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Mar 18 2017
STATUS
approved