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A221139 T(n,k) = number of n X k arrays of occupancy after each element moves to some horizontal or vertical neighbor, with no occupancy greater than 2. 7
0, 1, 1, 2, 9, 2, 4, 49, 49, 4, 8, 289, 656, 289, 8, 16, 1681, 12544, 12544, 1681, 16, 32, 9801, 200072, 643204, 200072, 9801, 32, 64, 57121, 3485689, 31203396, 31203396, 3485689, 57121, 64, 128, 332929, 58132316, 1539699121, 4235650596, 1539699121 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,4

COMMENTS

Table starts

....0........1............2...............4.................8

....1........9...........49.............289..............1681

....2.......49..........656...........12544............200072

....4......289........12544..........643204..........31203396

....8.....1681.......200072........31203396........4235650596

...16.....9801......3485689......1539699121......619901126244

...32....57121.....58132316.....75512292025....86907967843320

...64...332929....990486784...3709710975721.12474883501876324

..128..1940449..16699002692.182118668668225

..256.11309769.282999528529

..512.65918161

.1024

Even rows and columns are perfect squares.

LINKS

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

EXAMPLE

Some solutions for n=3, k=4:

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

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

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

CROSSREFS

Column 1 is A000079(n-2).

Column 2 is A090390.

Sequence in context: A153460 A342209 A248695 * A217273 A188981 A277754

Adjacent sequences:  A221136 A221137 A221138 * A221140 A221141 A221142

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin, Jan 02 2013

STATUS

approved

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Last modified October 16 19:46 EDT 2021. Contains 348044 sequences. (Running on oeis4.)