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A202048
Number of (n+2) X 6 binary arrays avoiding patterns 001 and 110 in rows and columns.
1
636, 1968, 4980, 11016, 22092, 41088, 71964, 120000, 192060, 296880, 445380, 651000, 930060, 1302144, 1790508, 2422512, 3230076, 4250160, 5525268, 7103976, 9041484, 11400192, 14250300, 17670432, 21748284, 26581296, 32277348, 38955480
OFFSET
1,1
COMMENTS
Column 4 of A202052.
LINKS
FORMULA
Empirical: a(n) = (1/30)*n^6 + (9/10)*n^5 + (59/6)*n^4 + (111/2)*n^3 + (2552/15)*n^2 + (1278/5)*n + 144.
Conjectures from Colin Barker, May 25 2018: (Start)
G.f.: 12*x*(53 - 207*x + 380*x^2 - 398*x^3 + 245*x^4 - 83*x^5 + 12*x^6) / (1 - x)^7.
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..0..0..0....0..0..0..0..0..0....1..0..1..0..1..0....1..0..0..0..0..0
..1..0..0..0..0..0....1..0..1..0..1..1....0..1..0..1..0..0....1..0..1..1..1..1
..0..1..0..0..0..0....0..0..0..0..0..0....1..0..0..0..0..0....1..0..0..0..0..0
..1..0..0..0..0..0....1..0..1..0..1..1....0..0..0..0..0..0....1..0..1..1..1..1
..0..0..0..0..0..0....1..0..0..0..0..0....1..0..0..0..0..0....1..0..1..1..1..1
CROSSREFS
Cf. A202052.
Sequence in context: A250581 A061623 A253506 * A251039 A203054 A198774
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 10 2011
STATUS
approved