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A221828
T(n,k)=Number of nXk arrays of occupancy after each element moves to some horizontal, vertical or antidiagonal neighbor, without 2-loops or left turns
8
0, 0, 0, 0, 3, 0, 0, 16, 14, 0, 0, 73, 202, 64, 0, 0, 333, 2879, 2930, 292, 0, 0, 1519, 40983, 115417, 41618, 1332, 0, 0, 6929, 583419, 4715043, 4755445, 592601, 6076, 0, 0, 31607, 8304016, 192788993, 570066685, 194407111, 8434490, 27716, 0, 0, 144177
OFFSET
1,5
COMMENTS
Table starts
.0......0..........0............0.............0..............0.............0
.0......3.........16...........73...........333...........1519..........6929
.0.....14........202.........2879.........40983.........583419.......8304016
.0.....64.......2930.......115417.......4715043......192788993....7888216533
.0....292......41618......4755445.....570066685....68573607669.8233561918895
.0...1332.....592601....194407111...68489860450.24121109763712
.0...6076....8434490...7954432829.8224749361083
.0..27716..120053263.325446165881
.0.126428.1708776751
.0.576708
.0
LINKS
FORMULA
Empirical for col 2: a(n) = 5*a(n-1) -2*a(n-2) for n>3
Empirical for row 2: a(k)=5*a(k-1)-2*a(k-2) for k>4
EXAMPLE
Some solutions for n=3 k=4
..0..1..1..0....1..2..1..1....1..1..0..2....0..2..0..1....1..1..1..1
..1..2..0..1....1..1..2..1....2..1..1..1....2..1..0..1....1..0..1..2
..2..1..2..1....0..0..1..1....1..1..1..0....1..2..1..1....1..1..2..0
CROSSREFS
Column 2 is A060801(n-1)
Sequence in context: A278208 A105786 A291802 * A368348 A278188 A101192
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin Jan 26 2013
STATUS
approved