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A231518 Number of nX3 0..1 arrays with no element less than a strict majority of its horizontal, diagonal and antidiagonal neighbors 1
4, 34, 153, 776, 3861, 18721, 91993, 453274, 2223662, 10915727, 53635324, 263420767, 1293604417, 6353594215, 31205396110, 153258629442, 752708346275, 3696838244354, 18156489259107, 89173024237567, 437961215793703 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Column 3 of A231523
LINKS
FORMULA
Empirical: a(n) = 4*a(n-1) -2*a(n-2) +43*a(n-3) -50*a(n-4) +33*a(n-5) -307*a(n-6) +115*a(n-7) -66*a(n-8) +490*a(n-9) +60*a(n-10) -144*a(n-11) +32*a(n-12) -192*a(n-13) for n>14
EXAMPLE
Some solutions for n=7
..0..1..0....0..0..1....1..0..1....0..0..1....1..0..0....1..0..0....1..0..0
..1..0..0....0..1..1....0..0..0....0..0..1....0..0..0....1..1..0....0..1..1
..1..0..0....0..0..0....1..0..0....0..0..0....1..1..0....1..0..0....1..0..0
..0..0..0....0..0..1....1..0..0....1..0..0....0..0..1....0..0..1....0..0..1
..0..0..0....1..0..0....0..0..0....0..0..1....0..0..0....0..0..0....1..1..0
..0..0..0....0..0..0....0..0..1....0..0..0....0..0..1....1..0..0....1..0..0
..0..0..1....0..1..0....1..0..0....1..1..1....1..1..1....0..0..1....0..0..0
CROSSREFS
Sequence in context: A241231 A297715 A129557 * A196908 A197075 A085695
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 10 2013
STATUS
approved

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Last modified June 18 04:26 EDT 2024. Contains 373468 sequences. (Running on oeis4.)