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A206201
Number of (n+1)X4 0..3 arrays with every 2X3 or 3X2 subblock having exactly one clockwise edge increases
1
1768, 3008, 5136, 11832, 27400, 60800, 145208, 346080, 775944, 1799656, 4265112, 9666256, 22287416, 52569856, 120132224, 276283624, 648644008, 1490750392, 3426149328, 8010922248, 18480112640, 42488361472, 99015558792, 228939593928
OFFSET
1,1
COMMENTS
Column 3 of A206206
LINKS
FORMULA
Empirical: a(n) = 10*a(n-3) +5*a(n-4) +a(n-5) +2*a(n-8) +2*a(n-10) for n>18
EXAMPLE
Some solutions for n=4
..0..3..1..1....0..2..1..1....3..3..1..0....0..0..2..2....1..0..0..0
..0..1..1..1....0..1..1..1....3..3..3..0....0..0..1..1....0..0..0..1
..1..1..1..3....1..1..1..0....1..3..3..3....0..1..1..1....0..0..1..1
..1..1..2..2....1..1..2..2....2..2..3..3....0..1..1..0....0..1..1..1
..1..2..2..2....1..2..2..2....2..2..2..2....0..0..0..0....0..1..1..0
CROSSREFS
Sequence in context: A031672 A031540 A135795 * A237900 A221118 A155023
KEYWORD
nonn
AUTHOR
R. H. Hardin Feb 04 2012
STATUS
approved