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A208778
Number of n X 6 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 1 1 and 1 1 1 vertically.
1
26, 676, 156, 260, 416, 676, 1092, 1768, 2860, 4628, 7488, 12116, 19604, 31720, 51324, 83044, 134368, 217412, 351780, 569192, 920972, 1490164, 2411136, 3901300, 6312436, 10213736, 16526172, 26739908, 43266080, 70005988, 113272068
OFFSET
1,1
COMMENTS
Column 6 of A208780.
LINKS
FORMULA
Empirical: a(n) = a(n-1) + a(n-2) for n>4.
Empirical g.f.: 26*x*(1 + 25*x - 21*x^2 - 22*x^3) / (1 - x - x^2). - Colin Barker, Jul 06 2018
EXAMPLE
Some solutions for n=4:
0 1 0 1 0 0 0 1 0 1 1 0 0 1 0 1 0 1 1 0 1 0 1 1
1 0 1 0 1 0 1 0 1 0 1 1 1 0 1 0 1 0 0 1 0 1 0 0
0 1 0 1 0 1 0 1 0 1 0 0 0 1 0 1 0 0 1 0 1 0 1 1
1 0 1 0 1 0 1 0 1 0 1 1 1 0 1 0 1 1 0 1 0 1 0 0
CROSSREFS
Cf. A208780.
Sequence in context: A158542 A171331 A097309 * A208499 A207587 A207843
KEYWORD
nonn
AUTHOR
R. H. Hardin, Mar 01 2012
STATUS
approved