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A281327
Number of 2Xn 0..2 arrays with no element equal to more than one of its horizontal and antidiagonal neighbors, with the exception of exactly one element, and with new values introduced in order 0 sequentially upwards.
1
0, 2, 46, 394, 3102, 22342, 153982, 1028164, 6712782, 43087434, 272912970, 1710241966, 10623835430, 65512041216, 401476483174, 2447254681866, 14848545047958, 89727018732086, 540259780322574, 3242602059388124
OFFSET
1,2
COMMENTS
Row 2 of A281326.
LINKS
FORMULA
Empirical: a(n) = 10*a(n-1) -13*a(n-2) -82*a(n-3) +60*a(n-4) +210*a(n-5) -77*a(n-6) -202*a(n-7) +39*a(n-8) +56*a(n-9) -16*a(n-10) for n>11
EXAMPLE
Some solutions for n=4
..0..1..2..1. .0..0..1..2. .0..1..0..2. .0..1..2..0. .0..1..2..0
..1..1..0..0. .0..2..1..0. .2..0..0..1. .1..1..0..2. .2..2..0..2
CROSSREFS
Cf. A281326.
Sequence in context: A071777 A179108 A158960 * A302377 A303098 A302949
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 20 2017
STATUS
approved