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A203085
Number of (n+2)X4 binary arrays avoiding patterns 000 and 101 in rows and columns
1
253, 787, 2237, 6615, 19723, 57699, 169561, 500813, 1473813, 4336509, 12776787, 37624405, 110768047, 326202095, 960592477, 2828495527, 8329036847, 24526561909, 72221962493, 212669436487, 626242809531, 1844074518231
OFFSET
1,1
COMMENTS
Column 2 of A203091
LINKS
FORMULA
Empirical: a(n) = a(n-1) +2*a(n-2) +10*a(n-3) +6*a(n-4) -5*a(n-5) -10*a(n-6) -8*a(n-7) +2*a(n-8) +10*a(n-9) -24*a(n-10) -20*a(n-11) +23*a(n-12) +22*a(n-13) -10*a(n-14)
EXAMPLE
Some solutions for n=3
..0..0..1..0....1..0..0..1....0..1..1..0....1..1..1..0....0..0..1..1
..0..1..1..0....1..1..0..0....1..0..0..1....1..0..0..1....0..0..1..1
..1..1..1..1....1..1..1..0....1..0..0..1....1..0..0..1....1..1..1..1
..1..0..0..1....1..1..1..1....1..1..1..0....0..1..1..1....0..1..1..1
..1..0..0..1....1..0..0..1....0..1..1..0....0..0..1..1....0..0..1..0
CROSSREFS
Sequence in context: A002289 A158078 A157356 * A245790 A070193 A054737
KEYWORD
nonn
AUTHOR
R. H. Hardin Dec 29 2011
STATUS
approved