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A188840
Number of n X 6 binary arrays without the pattern 0 1 diagonally or vertically.
1
64, 377, 1093, 2380, 4488, 7752, 12597, 19551, 29260, 42504, 60214, 83490, 113620, 152100, 200655, 261261, 336168, 427924, 539400, 673816, 834768, 1026256, 1252713, 1519035, 1830612, 2193360, 2613754, 3098862, 3656380, 4294668, 5022787, 5850537
OFFSET
1,1
COMMENTS
Column 6 of A188843.
LINKS
FORMULA
Empirical: a(n) = (1/720)*n^6 + (17/240)*n^5 + (203/144)*n^4 + (647/48)*n^3 + (2659/45)*n^2 + (1379/20)*n - 143 for n>3.
Empirical g.f.: x*(64 - 71*x - 202*x^2 + 406*x^3 - 174*x^4 - 88*x^5 + 67*x^6 + 6*x^7 - 6*x^8 - x^9) / (1 - x)^7. - Colin Barker, Apr 30 2018
EXAMPLE
Some solutions for 3 X 6:
..1..1..1..1..1..1....1..1..1..1..1..1....0..0..0..1..1..0....1..1..1..1..1..1
..1..1..1..1..1..1....0..0..1..1..1..1....0..0..0..0..1..0....1..1..1..1..0..0
..0..0..1..1..0..1....0..0..0..1..1..0....0..0..0..0..0..0....1..1..0..1..0..0
CROSSREFS
Cf. A188843.
Sequence in context: A344302 A105918 A224042 * A188703 A297343 A228759
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 12 2011
STATUS
approved