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A208381 Number of 5 X n 0..1 arrays avoiding 0 0 0 and 1 1 1 horizontally and 0 0 1 and 1 0 1 vertically. 1
10, 100, 144, 640, 2176, 7072, 25200, 87040, 296560, 1028128, 3545856, 12198016, 42085264, 145092160, 499958928, 1723635712, 5941670272, 20479942816, 70597050480, 243353573632, 838843117552, 2891546321440, 9967326856704 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Row 5 of A208379.
LINKS
FORMULA
Empirical: a(n) = a(n-1) + 4*a(n-2) + 13*a(n-3) + 8*a(n-4) - 3*a(n-5) + 9*a(n-6) for n>8.
Empirical g.f.: 2*x*(5 + 45*x + 2*x^2 - 17*x^3 - 210*x^4 - 153*x^5 + 81*x^6 - 162*x^7) / (1 - x - 4*x^2 - 13*x^3 - 8*x^4 + 3*x^5 - 9*x^6). - Colin Barker, Jul 02 2018
EXAMPLE
Some solutions for n=4:
..1..0..1..1....1..1..0..0....1..1..0..0....0..1..0..1....1..0..1..0
..0..1..0..0....0..0..1..1....1..1..0..0....0..1..1..0....1..0..1..0
..0..1..0..0....0..0..1..1....0..1..0..0....0..1..0..0....0..0..1..0
..0..1..0..0....0..0..1..0....0..1..0..0....0..1..0..0....0..0..1..0
..0..1..0..0....0..0..1..0....0..1..0..0....0..1..0..0....0..0..1..0
CROSSREFS
Cf. A208379.
Sequence in context: A116143 A208497 A207585 * A031187 A029797 A367593
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 25 2012
STATUS
approved

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Last modified April 20 02:53 EDT 2024. Contains 371798 sequences. (Running on oeis4.)