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A221810
Number of 2Xn arrays of occupancy after each element moves to some horizontal, vertical or antidiagonal neighbor, without move-in move-out straight through or left turns
1
1, 10, 34, 214, 1016, 5429, 27535, 142858, 733811, 3785852, 19494390, 100466360, 517573094, 2666814576, 13739888978, 70792474153, 364741397621, 1879254550345, 9682444806825, 49886719497414, 257030490240855, 1324294082316952
OFFSET
1,2
COMMENTS
Row 2 of A221809
LINKS
FORMULA
Empirical: a(n) = a(n-1) +18*a(n-2) +22*a(n-3) -14*a(n-4) -39*a(n-5) -44*a(n-6) -6*a(n-7) +7*a(n-8) +3*a(n-9) +4*a(n-10) +a(n-11)
EXAMPLE
Some solutions for n=3
..1..0..1....1..1..1....1..1..1....2..1..1....1..0..1....0..2..1....1..2..0
..2..1..1....2..0..1....1..2..0....0..1..1....1..1..2....1..2..0....0..3..0
CROSSREFS
Sequence in context: A341300 A232902 A001890 * A219591 A272365 A230895
KEYWORD
nonn
AUTHOR
R. H. Hardin Jan 26 2013
STATUS
approved