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A208711
Number of 4Xn 0..1 arrays with new values 0..1 introduced in row major order and no element equal to more than two of its immediate leftward or upward or right-upward antidiagonal neighbors
1
8, 128, 1372, 16084, 185344, 2142580, 24754628, 286034292, 3305009328, 38188137788, 441249345280, 5098468022268, 58910854227068, 680692462409636, 7865141904908344, 90878716312611076, 1050068921631026592
OFFSET
1,1
COMMENTS
Row 4 of A208709
LINKS
FORMULA
Empirical: a(n) = 9*a(n-1) +31*a(n-2) -11*a(n-3) -71*a(n-4) -a(n-5) +38*a(n-6) -8*a(n-7) for n>9
EXAMPLE
Some solutions for n=4
..0..1..0..1....0..1..0..1....0..1..1..0....0..0..0..1....0..0..0..1
..1..0..1..1....1..1..0..1....0..0..1..0....1..0..1..1....1..0..0..0
..0..0..0..1....0..1..1..0....0..0..1..1....0..0..1..0....1..1..1..1
..0..1..0..1....0..0..1..1....1..0..0..0....0..1..0..0....1..0..1..1
CROSSREFS
Sequence in context: A303471 A301998 A105094 * A242355 A305519 A316956
KEYWORD
nonn
AUTHOR
R. H. Hardin Mar 01 2012
STATUS
approved