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A270150 T(n,k)=Number of nXk 0..7 arrays with some element plus some horizontally, diagonally, antidiagonally or vertically adjacent neighbor totalling seven exactly once. 6
0, 8, 8, 112, 1440, 112, 1176, 85056, 85056, 1176, 10976, 4126368, 24250368, 4126368, 10976, 96040, 182257536, 5750902944, 5750902944, 182257536, 96040, 806736, 7623445344, 1246566350496, 6697695002208, 1246566350496, 7623445344, 806736 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Table starts

.....0..........8.............112................1176....................10976

.....8.......1440...........85056.............4126368................182257536

...112......85056........24250368..........5750902944............1246566350496

..1176....4126368......5750902944.......6697695002208.........7142783643783792

.10976..182257536...1246566350496....7142783643783792.....37516051668350707200

.96040.7623445344.256330155581328.7232246139319438944.187171034679828236009184

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..84

FORMULA

Empirical for column k:

k=1: a(n) = 14*a(n-1) -49*a(n-2)

k=2: a(n) = 66*a(n-1) -1021*a(n-2) -2244*a(n-3) -1156*a(n-4) for n>5

k=3: [order 10] for n>11

k=4: [order 30] for n>31

EXAMPLE

Some solutions for n=2 k=4

..0..4..7..5. .0..2..6..2. .0..3..1..1. .0..0..4..7. .0..2..7..6

..0..4..2..1. .0..5..0..6. .0..6..5..1. .0..0..4..0. .4..2..4..0

CROSSREFS

Column 1 is A270111.

Sequence in context: A192386 A119932 A270118 * A065241 A255006 A074191

Adjacent sequences:  A270147 A270148 A270149 * A270151 A270152 A270153

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin, Mar 12 2016

STATUS

approved

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Last modified April 18 16:56 EDT 2019. Contains 322229 sequences. (Running on oeis4.)