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A231822
Number of n X 2 0..2 arrays with no element having a strict majority of its horizontal, vertical and antidiagonal neighbors equal to itself plus one mod 3, with upper left element zero (rock paper and scissors drawn positions).
1
1, 9, 64, 439, 2992, 20382, 138852, 945923, 6444056, 43899870, 299066137, 2037376372, 13879547189, 94553875250, 644144597665, 4388210021417, 29894510123024, 203655187692590, 1387393046555052, 9451561177738998
OFFSET
1,2
LINKS
FORMULA
Empirical: a(n) = 9*a(n-1) - 16*a(n-2) + 11*a(n-3) - 27*a(n-4) + 21*a(n-5) - 4*a(n-6).
Empirical g.f.: x*(1 - x^2 - 4*x^3 - 7*x^4 - 4*x^5) / (1 - 9*x + 16*x^2 - 11*x^3 + 27*x^4 - 21*x^5 + 4*x^6). - Colin Barker, Oct 01 2018
EXAMPLE
Some solutions for n=7:
..0..0....0..0....0..0....0..1....0..0....0..0....0..0....0..0....0..0....0..0
..1..0....2..1....1..2....0..1....1..0....2..1....2..1....0..1....2..1....2..2
..2..2....1..2....1..1....0..2....0..2....2..1....1..1....2..1....1..2....2..0
..2..0....1..2....1..1....1..2....2..2....1..0....0..2....1..2....1..1....1..1
..1..0....0..1....2..2....1..0....2..2....2..2....0..1....1..0....2..0....2..2
..2..0....0..2....0..0....2..2....2..2....2..2....1..1....2..1....0..0....0..0
..2..1....1..1....0..1....0..1....2..2....0..1....2..0....0..2....1..2....1..1
CROSSREFS
Column 2 of A231828.
Sequence in context: A083328 A000846 A357649 * A049684 A037540 A037484
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 14 2013
STATUS
approved