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A231382 T(n,k)=Number of nXk 0..1 arrays with no element less than a strict majority of its horizontal and vertical neighbors 8
2, 2, 2, 4, 10, 4, 7, 21, 21, 7, 12, 48, 93, 48, 12, 21, 113, 378, 378, 113, 21, 37, 261, 1519, 2539, 1519, 261, 37, 65, 601, 6126, 17363, 17363, 6126, 601, 65, 114, 1390, 24747, 120124, 209118, 120124, 24747, 1390, 114, 200, 3216, 99964, 830890, 2547810 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Table starts

...2....2.......4.........7..........12.............21...............37

...2...10......21........48.........113............261..............601

...4...21......93.......378........1519...........6126............24747

...7...48.....378......2539.......17363.........120124...........830890

..12..113....1519.....17363......209118........2547810.........30936914

..21..261....6126....120124.....2547810.......54485279.......1157805351

..37..601...24747....830890....30936914.....1157805351......42978519280

..65.1390...99964...5746499...375620622....24615811883....1597438228604

.114.3216..403743..39745115..4560995236...523548909308...59402875813957

.200.7435.1630662.274872588.55375119088.11133382117666.2208383979206654

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..312

FORMULA

Empirical for column k:

k=1: a(n) = 2*a(n-1) -a(n-2) +a(n-3) for n>4

k=2: a(n) = 3*a(n-1) -2*a(n-2) +2*a(n-3) -2*a(n-4) -a(n-5) for n>6

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

k=4: [order 19] for n>20

k=5: [order 46] for n>47

EXAMPLE

Some solutions for n=3 k=4

..1..0..0..0....0..0..0..1....1..0..0..0....1..0..0..0....0..1..1..0

..0..0..1..1....1..1..0..0....0..0..1..1....0..0..1..0....0..0..0..0

..0..0..0..0....1..1..0..0....0..0..1..1....0..0..1..0....0..0..1..1

CROSSREFS

Column 1 is A005251(n+2)

Sequence in context: A153986 A199889 A293177 * A213270 A307522 A130707

Adjacent sequences:  A231379 A231380 A231381 * A231383 A231384 A231385

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin, Nov 08 2013

STATUS

approved

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Last modified January 28 00:32 EST 2020. Contains 331313 sequences. (Running on oeis4.)