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A202594
Number of (n+2) X 3 binary arrays avoiding patterns 001 and 000 in rows and columns.
1
126, 510, 1968, 7722, 30114, 117708, 459690, 1795842, 7014816, 27402198, 107040102, 418129380, 1633329054, 6380241774, 24923005584, 97356232314, 380300658210, 1485560712012, 5803015490538, 22668201049266, 88548331298112
OFFSET
1,1
COMMENTS
Column 1 of A202601.
LINKS
FORMULA
Empirical: a(n) = 2*a(n-1) +7*a(n-2) +2*a(n-3) -a(n-4).
Empirical g.f.: 6*x*(21 + 43*x + 11*x^2 - 6*x^3) / (1 - 2*x - 7*x^2 - 2*x^3 + x^4). - Colin Barker, Jun 01 2018
EXAMPLE
Some solutions for n=3:
..0..1..1....1..0..1....1..1..1....1..0..0....0..1..0....1..1..0....1..1..0
..1..0..0....1..1..1....1..0..1....0..1..1....1..1..1....0..1..1....1..0..1
..0..1..1....0..1..1....1..1..1....1..0..1....0..1..1....1..0..1....1..1..1
..1..1..0....1..1..1....1..1..1....1..1..0....1..0..1....0..1..1....0..1..1
..1..0..0....0..1..1....1..0..1....1..1..1....1..0..1....0..1..0....1..0..0
CROSSREFS
Cf. A202601.
Sequence in context: A135192 A154039 A202601 * A245992 A267566 A165023
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 21 2011
STATUS
approved