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A188839
Number of n X 5 binary arrays without the pattern 0 1 diagonally or vertically.
1
32, 144, 364, 728, 1288, 2108, 3264, 4845, 6954, 9709, 13244, 17710, 23276, 30130, 38480, 48555, 60606, 74907, 91756, 111476, 134416, 160952, 191488, 226457, 266322, 311577, 362748, 420394, 485108, 557518, 638288, 728119, 827750, 937959, 1059564
OFFSET
1,1
COMMENTS
Column 5 of A188843.
LINKS
FORMULA
Empirical: a(n) = (1/120)*n^5 + (7/24)*n^4 + (89/24)*n^3 + (473/24)*n^2 + (1877/60)*n - 33 for n>2.
Empirical g.f.: x*(32 - 48*x - 20*x^2 + 64*x^3 - 20*x^4 - 12*x^5 + 4*x^6 + x^7) / (1 - x)^6. - Colin Barker, Apr 30 2018
EXAMPLE
Some solutions for 3 X 5:
..1..1..0..0..1....0..1..1..1..1....1..1..1..0..1....1..1..1..1..1
..1..1..0..0..0....0..0..0..0..0....1..1..1..0..0....0..1..0..1..0
..0..1..0..0..0....0..0..0..0..0....1..0..1..0..0....0..0..0..0..0
CROSSREFS
Cf. A188843.
Sequence in context: A048191 A363531 A224041 * A188702 A297342 A228758
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 12 2011
STATUS
approved