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A283494
T(n,k)=Number of nXk 0..1 arrays with no 1 equal to more than three of its horizontal, vertical and antidiagonal neighbors, with the exception of exactly one element.
7
0, 0, 0, 0, 0, 0, 0, 2, 2, 0, 0, 12, 59, 12, 0, 0, 64, 576, 576, 64, 0, 0, 312, 5444, 10000, 5444, 312, 0, 0, 1460, 47712, 174232, 174232, 47712, 1460, 0, 0, 6624, 402588, 2836520, 5691512, 2836520, 402588, 6624, 0, 0, 29394, 3304736, 44556288
OFFSET
1,8
COMMENTS
Table starts
.0.....0........0...........0.............0................0..................0
.0.....0........2..........12............64..............312...............1460
.0.....2.......59.........576..........5444............47712.............402588
.0....12......576.......10000........174232..........2836520...........44556288
.0....64.....5444......174232.......5691512........173139952.........5074155320
.0...312....47712.....2836520.....173139952.......9816981756.......536229705204
.0..1460...402588....44556288....5074155320.....536229705204.....54620836862500
.0..6624..3304736...682531252..145077026768...28589370541536...5432594465187864
.0.29394.26585976.10259419732.4069261870596.1495349029171972.530096184197639160
LINKS
FORMULA
Empirical for column k:
k=1: a(n) = a(n-1)
k=2: [order 10]
k=3: [order 10] for n>13
k=4: [order 26] for n>29
k=5: [order 74] for n>77
EXAMPLE
Some solutions for n=4 k=4
..0..1..1..0. .0..1..1..1. .1..1..0..0. .1..1..0..1. .0..1..0..0
..0..1..1..0. .0..0..1..1. .0..1..0..1. .0..1..1..1. .1..1..1..1
..1..1..0..0. .1..0..1..0. .0..0..1..1. .0..0..1..0. .0..1..0..0
..0..0..1..0. .0..0..1..0. .1..1..1..0. .0..0..0..1. .0..0..1..1
CROSSREFS
Sequence in context: A037224 A122670 A352661 * A353254 A281034 A282441
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Mar 08 2017
STATUS
approved