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A269186 T(n,k)=Number of nXk 0..3 arrays with some element plus some horizontally, diagonally, antidiagonally or vertically adjacent neighbor totalling three exactly once. 8
0, 4, 4, 24, 48, 24, 108, 384, 384, 108, 432, 2736, 5888, 2736, 432, 1620, 18336, 80112, 80112, 18336, 1620, 5832, 118032, 1031344, 2097552, 1031344, 118032, 5832, 20412, 739008, 12791896, 52394312, 52394312, 12791896, 739008, 20412, 69984, 4533744 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Table starts

......0.........4...........24.............108................432

......4........48..........384............2736..............18336

.....24.......384.........5888...........80112............1031344

....108......2736........80112.........2097552...........52394312

....432.....18336......1031344........52394312.........2563440512

...1620....118032.....12791896......1265974992.......121792778352

...5832....739008....154606864.....29881402560......5665397992608

..20412...4533744...1833130768....693021071760....259306140235672

..69984..27384288..21416076480..15854541802056..11718368891185840

.236196.163381968.247279304248.358760880894864.524154208020159720

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..219

FORMULA

Empirical for column k:

k=1: a(n) = 6*a(n-1) -9*a(n-2)

k=2: a(n) = 10*a(n-1) -21*a(n-2) -20*a(n-3) -4*a(n-4) for n>5

k=3: [order 8] for n>9

k=4: [order 16] for n>17

k=5: [order 40] for n>41

EXAMPLE

Some solutions for n=3 k=4

..3..3..3..2. .2..3..1..3. .1..1..2..0. .2..2..2..3. .3..1..2..3

..1..1..3..1. .2..3..3..2. .0..0..0..0. .0..0..2..0. .1..3..3..3

..3..1..1..1. .3..3..2..2. .1..1..0..2. .2..2..0..0. .3..1..1..3

CROSSREFS

Column 1 is A120908.

Sequence in context: A088304 A131978 A049614 * A058166 A092897 A269152

Adjacent sequences:  A269183 A269184 A269185 * A269187 A269188 A269189

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin, Feb 20 2016

STATUS

approved

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Last modified June 25 05:41 EDT 2019. Contains 324346 sequences. (Running on oeis4.)