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A221381 T(n,k)=Number of nXk arrays of occupancy after each element moves to some horizontal or antidiagonal neighbor, with every occupancy equal to zero or two 4
0, 0, 0, 0, 1, 0, 1, 2, 0, 0, 0, 4, 0, 1, 0, 0, 8, 9, 4, 0, 0, 0, 16, 0, 25, 0, 1, 0, 1, 32, 0, 189, 64, 8, 0, 0, 0, 64, 0, 1156, 0, 169, 0, 1, 0, 0, 128, 1225, 6996, 0, 5040, 441, 16, 0, 0, 0, 256, 0, 43681, 0, 120409, 0, 1156, 0, 1, 0, 1, 512, 0, 268632, 1397124, 2284160, 0, 134521 (list; table; graph; refs; listen; history; text; internal format)
OFFSET
1,8
COMMENTS
Table starts
.0.0..0.....1.......0..........0.........0...........1.........0...........0
.0.1..2.....4.......8.........16........32..........64.......128.........256
.0.0..0.....9.......0..........0.........0........1225.........0...........0
.0.1..4....25.....189.......1156......6996.......43681....268632.....1664100
.0.0..0....64.......0..........0.........0.....1397124.........0...........0
.0.1..8...169....5040.....120409...2284160....47527236.875241328.17328299769
.0.0..0...441.......0..........0.........0..1599280081.........0...........0
.0.1.16..1156..134521...13075456.763775056.54143705344
.0.0..0..3025.......0..........0.........0
.0.1.32..7921.3580920.1425817600
.0.0..0.20736.......0
.0.1.64.54289
Even columns are perfect squares
LINKS
EXAMPLE
Some solutions for n=3 k=4
..0..2..2..0....0..2..2..0....0..2..2..2....0..2..0..2....0..2..2..0
..0..2..2..2....0..2..0..2....0..0..2..0....2..0..2..0....0..2..2..0
..0..0..2..0....2..0..2..0....0..2..2..0....0..2..2..0....0..2..2..0
CROSSREFS
Column 4 is A007598(n+1)
Sequence in context: A204531 A113277 A114855 * A100951 A348616 A348613
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin Jan 14 2013
STATUS
approved

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Last modified April 23 13:11 EDT 2024. Contains 371913 sequences. (Running on oeis4.)