A231518 Number of nX3 0..1 arrays with no element less than a strict majority of its horizontal, diagonal and antidiagonal neighbors

4, 34, 153, 776, 3861, 18721, 91993, 453274, 2223662, 10915727, 53635324, 263420767, 1293604417, 6353594215, 31205396110, 153258629442, 752708346275, 3696838244354, 18156489259107, 89173024237567, 437961215793703

Offset

1,1

Comments

Column 3 of A231523

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

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

Adjacent sequences: A231515 A231516 A231517 * A231519 A231520 A231521

Keyword

nonn

Author

R. H. Hardin, Nov 10 2013

Status

approved