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A202531 Number of (n+2) X 9 binary arrays avoiding patterns 000 and 101 in rows, columns and nw-to-se diagonals. 1
8994, 22525, 47098, 97936, 214388, 462445, 986000, 2119913, 4562593, 9790618, 21022108, 45171964, 97022597, 208368988, 447576365, 961372373, 2064884218, 4435160104, 9526346212, 20461585981, 43949347976, 94398876097, 202759283897 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Column 7 of A202532.
LINKS
FORMULA
Empirical: a(n) = 2*a(n-1) +2*a(n-3) -2*a(n-4) -2*a(n-5) +a(n-7) for n>8.
Empirical g.f.: x*(8994 + 4537*x + 2048*x^2 - 14248*x^3 - 8546*x^4 + 2511*x^5 + 4484*x^6 + 211*x^7) / ((1 - x)*(1 + x^2 - x^3)*(1 - x - 2*x^2 - x^3)). - Colin Barker, Jun 01 2018
EXAMPLE
Some solutions for n=3:
..1..0..0..1..1..1..1..1..0....1..0..0..1..1..0..0..1..1
..1..1..1..1..1..1..1..1..0....1..1..1..1..1..1..1..1..1
..0..1..1..1..1..1..1..1..1....1..1..1..1..1..1..1..1..1
..0..1..1..1..1..1..1..1..1....1..1..1..1..1..1..1..1..1
..1..1..1..1..0..0..1..1..0....0..1..1..1..1..0..0..1..1
CROSSREFS
Cf. A202532.
Sequence in context: A144126 A263062 A215198 * A106770 A326319 A102484
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 20 2011
STATUS
approved

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Last modified March 28 20:05 EDT 2024. Contains 371254 sequences. (Running on oeis4.)