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A202049
Number of (n+2) X 7 binary arrays avoiding patterns 001 and 110 in rows and columns.
1
966, 3304, 9170, 22092, 47950, 95984, 180054, 320180, 544390, 890904, 1410682, 2170364, 3255630, 4775008, 6864158, 9690660, 13459334, 18418120, 24864546, 33152812, 43701518, 57002064, 73627750, 94243604, 119616966, 150628856
OFFSET
1,1
COMMENTS
Column 5 of A202052.
LINKS
FORMULA
Empirical: a(n) = (1/180)*n^7 + (7/36)*n^6 + (511/180)*n^5 + (805/36)*n^4 + (4606/45)*n^3 + (2443/9)*n^2 + (1854/5)*n + 196.
Conjectures from Colin Barker, May 26 2018: (Start)
G.f.: 14*x*(69 - 316*x + 699*x^2 - 918*x^3 + 755*x^4 - 384*x^5 + 111*x^6 - 14*x^7) / (1 - x)^8.
a(n) = 8*a(n-1) - 28*a(n-2) + 56*a(n-3) - 70*a(n-4) + 56*a(n-5) - 28*a(n-6) + 8*a(n-7) - a(n-8) for n>8.
(End)
EXAMPLE
Some solutions for n=3:
..0..1..0..1..0..1..0....0..1..1..1..1..1..1....0..1..0..1..0..0..0
..1..0..1..0..1..0..1....1..0..1..0..1..0..0....1..0..1..1..1..1..1
..0..1..0..1..0..1..0....1..1..1..1..1..1..1....0..1..0..1..0..0..0
..0..0..0..0..0..0..0....1..0..1..0..1..0..1....0..1..0..1..0..1..0
..0..1..0..0..0..0..0....1..0..1..0..1..1..1....0..1..0..1..0..0..0
CROSSREFS
Cf. A202052.
Sequence in context: A014363 A260291 A251232 * A246477 A064258 A142378
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 10 2011
STATUS
approved