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A220748
Equals one maps: number of nX3 binary arrays indicating the locations of corresponding elements equal to exactly one of their horizontal and vertical neighbors in a random 0..3 nX3 array
1
4, 38, 395, 3778, 32178, 261356, 2096110, 16776148, 134216342, 1073740504, 8589932829, 68719475152, 549755811711, 4398046509244, 35184372086204, 281474976708508, 2251799813682132, 18014398509479536, 144115188075852231
OFFSET
1,1
COMMENTS
Column 3 of A220751
LINKS
FORMULA
Empirical: a(n) = 8*a(n-1) +3*a(n-2) -24*a(n-3) -3*a(n-4) +24*a(n-5) +a(n-6) -8*a(n-7) for n>14
EXAMPLE
Some solutions for n=3
..0..1..1....1..1..1....0..1..1....0..0..0....0..1..0....0..1..0....0..0..1
..0..0..0....1..1..0....1..0..1....1..1..0....0..0..0....0..1..0....0..0..0
..0..0..0....0..0..1....0..1..0....0..1..1....1..0..0....1..0..1....0..1..1
CROSSREFS
Sequence in context: A221021 A155859 A220543 * A192947 A234463 A194044
KEYWORD
nonn
AUTHOR
R. H. Hardin Dec 18 2012
STATUS
approved