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A251219 T(n,k)=Number of (n+1)X(k+1) 0..1 arrays with no 2X2 subblock having zero or two 1s 9
9, 21, 21, 49, 63, 49, 115, 191, 191, 115, 269, 589, 758, 589, 269, 631, 1807, 3089, 3089, 1807, 631, 1477, 5569, 12503, 16911, 12503, 5569, 1477, 3463, 17119, 50912, 91777, 91777, 50912, 17119, 3463, 8109, 52713, 206715, 502971, 666522, 502971, 206715 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Table starts

.....9.....21.......49.......115.........269..........631...........1477

....21.....63......191.......589........1807.........5569..........17119

....49....191......758......3089.......12503........50912.........206715

...115....589.....3089.....16911.......91777.......502971........2746607

...269...1807....12503.....91777......666522......4907873.......35978029

...631...5569....50912....502971.....4907873.....48781920......482274751

..1477..17119...206715...2746607....35978029....482274751.....6424279907

..3463..52713...840931..15040763...264753513...4791965557....86110233175

..8109.162143..3417338..82261821..1945208633..47523048960..1151625700234

.19007.499081.13896689.450304289.14308155872.471984045011.15428988432635

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..364

FORMULA

Empirical for column k:

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

k=2: a(n) = 3*a(n-1) +4*a(n-2) -12*a(n-3) +4*a(n-5)

k=3: [order 9]

k=4: [order 16]

k=5: [order 32]

k=6: [order 62]

EXAMPLE

Some solutions for n=4 k=4

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

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

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

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

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

CROSSREFS

Sequence in context: A161326 A250783 A259250 * A284131 A111171 A317789

Adjacent sequences:  A251216 A251217 A251218 * A251220 A251221 A251222

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin, Nov 30 2014

STATUS

approved

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Last modified September 21 01:46 EDT 2021. Contains 347596 sequences. (Running on oeis4.)