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A208641
Number of 6 X n 0..1 arrays with new values 0..1 introduced in row major order and no element equal to more than one of its immediate leftward or upward or right-upward antidiagonal neighbors
1
32, 233, 851, 2331, 5572, 12404, 26508, 55260, 113427, 230559, 465773, 937321, 1881726, 3772054, 7554458, 15121266, 30257157, 60531513, 121083123, 242189591, 484406152, 968843304, 1937722072, 3875484536, 7751014887, 15502081539
OFFSET
1,1
COMMENTS
Row 6 of A208637.
LINKS
FORMULA
Empirical: a(n) = 7*a(n-1) - 20*a(n-2) + 30*a(n-3) - 25*a(n-4) + 11*a(n-5) - 2*a(n-6) for n>9.
Conjectures from Colin Barker, Jul 05 2018: (Start)
G.f.: x*(32 + 9*x - 140*x^2 + 74*x^3 + 85*x^4 - 37*x^5 - 34*x^6 + 4*x^7 + 8*x^8) / ((1 - x)^5*(1 - 2*x)).
a(n) = (792*(7*2^n-10) - 3382*n - 539*n^2 - 38*n^3 - n^4) / 24 for n>3.
(End)
EXAMPLE
Some solutions for n=4:
..0..1..0..1....0..0..0..1....0..0..0..1....0..0..0..0....0..1..0..1
..0..1..0..0....1..1..0..1....1..1..0..0....1..1..1..0....0..1..0..0
..0..1..1..0....0..1..0..1....0..1..1..0....0..0..1..1....1..0..1..0
..0..0..1..0....0..1..0..0....0..0..1..1....1..0..0..1....0..1..0..1
..1..0..1..1....0..1..1..1....1..0..0..1....1..1..0..1....1..0..1..0
..1..0..0..0....1..0..0..0....1..1..0..0....0..1..0..0....1..0..1..1
CROSSREFS
Cf. A208637.
Sequence in context: A199913 A301795 A301968 * A301889 A302085 A229400
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 29 2012
STATUS
approved