A231192 Number of (n+1) X (1+1) 0..2 arrays with no element equal to a strict majority of its horizontal, vertical and antidiagonal neighbors, with values 0..2 introduced in row major order.

9, 67, 538, 4264, 33868, 268936, 2135636, 16959144, 134673104, 1069443392, 8492483984, 67439085424, 535535922336, 4252707792768, 33770887846016, 268175694518400, 2129591719896640, 16911155582525312, 134292024365242368

Offset

1,1

Links

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

Formula

Empirical: a(n) = 8*a(n-1) - 4*a(n-3) + 4*a(n-4) - 12*a(n-5) - 16*a(n-6).

Empirical g.f.: x*(9 - 5*x + 2*x^2 - 4*x^3 - 12*x^4 - 16*x^5) / (1 - 8*x + 4*x^3 - 4*x^4 + 12*x^5 + 16*x^6). - Colin Barker, Sep 27 2018

Example

Some solutions for n=5:
..0..1....0..1....0..1....0..1....0..1....0..1....0..1....0..1....0..0....0..1
..2..2....2..2....2..2....1..0....1..0....2..2....0..1....2..0....1..2....1..2
..0..0....0..0....2..0....2..0....0..0....0..2....0..0....2..0....2..0....1..2
..2..1....2..1....0..2....1..2....2..1....2..0....2..2....0..2....1..0....1..0
..0..0....1..0....2..0....2..2....2..2....0..2....0..0....0..2....0..2....0..1
..2..2....2..2....1..0....1..0....0..0....0..2....1..1....1..0....0..2....2..1

Crossrefs

Column 1 of A231199.

Sequence in context: A287817 A155592 A002051 * A133120 A194650 A048742

Adjacent sequences: A231189 A231190 A231191 * A231193 A231194 A231195

Keyword

nonn

Author

R. H. Hardin, Nov 05 2013

Status

approved