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URL: https://oeis.org/A221139

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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
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
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 A388379
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Jan 02 2013
STATUS
approved