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A202197
Number of (n+2) X 5 binary arrays avoiding patterns 001 and 101 in rows and columns.
1
450, 1400, 3500, 7560, 14700, 26400, 44550, 71500, 110110, 163800, 236600, 333200, 459000, 620160, 823650, 1077300, 1389850, 1771000, 2231460, 2783000, 3438500, 4212000, 5118750, 6175260, 7399350, 8810200, 10428400, 12276000, 14376560
OFFSET
1,1
COMMENTS
Column 3 of A202202.
LINKS
FORMULA
Empirical: a(n) = 5*(n+5)*(n+4)*(n+3)*(n+2)^2/12.
Conjectures from Colin Barker, May 27 2018: (Start)
G.f.: 10*x*(45 - 130*x + 185*x^2 - 144*x^3 + 59*x^4 - 10*x^5) / (1 - x)^6.
a(n) = 6*a(n-1) - 15*a(n-2) + 20*a(n-3) - 15*a(n-4) + 6*a(n-5) - a(n-6) for n>6.
(End)
EXAMPLE
Some solutions for n=4:
..1..1..1..0..0....1..1..1..0..0....0..0..0..0..0....0..1..0..0..0
..1..1..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....0..1..1..0..0
..0..1..0..0..0....0..1..1..1..1....0..1..1..0..0....0..1..1..0..0
..0..1..0..0..0....0..1..1..1..1....0..0..0..0..0....0..1..1..0..0
..0..0..0..0..0....0..1..1..1..0....0..0..0..0..0....0..1..1..0..0
CROSSREFS
Cf. A202202.
Sequence in context: A351947 A079659 A304511 * A253750 A253743 A253369
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 14 2011
STATUS
approved