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A233230 T(n,k)=Number of nXk 0..5 arrays with no element x(i,j) adjacent to value 5-x(i,j) horizontally, diagonally, antidiagonally or vertically, top left element zero, and 1 appearing before 2 3 and 4, and 2 appearing before 3 in row major order 7
1, 2, 2, 6, 14, 6, 23, 174, 174, 23, 99, 2541, 8231, 2541, 99, 452, 39203, 420948, 420948, 39203, 452, 2136, 616454, 21895530, 72049266, 21895530, 616454, 2136, 10313, 9757236, 1142726121, 12389989684, 12389989684, 1142726121, 9757236, 10313 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Table starts

......1...........2................6.....................23

......2..........14..............174...................2541

......6.........174.............8231.................420948

.....23........2541...........420948...............72049266

.....99.......39203.........21895530............12389989684

....452......616454.......1142726121..........2131764323784

...2136.....9757236......59679029456........366805442634477

..10313...154782591....3117164734533......63115455429961173

..50469..2457231917..162820623245643...10860156414181066717

.249062.39019481264.8504746957840386.1868686679256045815893

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..112

FORMULA

Empirical for column k:

k=1: a(n) = 9*a(n-1) -23*a(n-2) +15*a(n-3)

k=2: a(n) = 21*a(n-1) -79*a(n-2) -41*a(n-3) +72*a(n-4) +28*a(n-5)

k=3: [order 10]

k=4: [order 23]

EXAMPLE

Some solutions for n=3 k=4

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

..1..0..2..5....3..0..1..1....1..0..2..2....1..0..2..4....0..0..2..2

..1..0..1..1....3..0..2..5....1..1..1..1....1..2..4..5....0..1..1..0

CROSSREFS

Column 1 is A233106

Sequence in context: A049952 A019100 A019101 * A320070 A319866 A266007

Adjacent sequences:  A233227 A233228 A233229 * A233231 A233232 A233233

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin, Dec 06 2013

STATUS

approved

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Last modified October 22 22:35 EDT 2021. Contains 348180 sequences. (Running on oeis4.)