A231264 Number of (2+1) X (n+1) 0..2 arrays with no element unequal to a strict majority of its horizontal and antidiagonal neighbors, with values 0..2 introduced in row major order.

6, 15, 32, 83, 211, 557, 1471, 3909, 10387, 27617, 73419, 195197, 518979, 1379897, 3669051, 9755861, 25940515, 68974961, 183402043, 487659661, 1296670403, 3447803113, 9167594299, 24376331077, 64815862051, 172343243361, 458255009275

Offset

1,1

Comments

Row 2 of A231263.

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) -8*a(n-3) +11*a(n-4) -4*a(n-6) -4*a(n-7) -4*a(n-8) +8*a(n-9).

Empirical g.f.: x*(6 - 9*x - 16*x^2 + 33*x^3 - 3*x^4 - 30*x^5 + x^6 - 2*x^7 + 40*x^8) / ((1 - x)*(1 + x)*(1 - 2*x + 2*x^2)*(1 - 2*x^2)*(1 - 2*x - x^2 - 2*x^3)). - Colin Barker, Feb 16 2018

Example

Some solutions for n=3:
..0..0..0..0....0..0..0..1....0..0..0..0....0..0..0..0....0..0..0..0
..0..0..1..1....0..0..1..1....1..1..2..2....0..0..0..0....1..1..1..0
..1..1..1..1....0..1..1..1....1..2..2..2....1..1..1..1....1..1..0..0

Crossrefs

Sequence in context: A273764 A273853 A192747 * A121666 A186829 A231452

Adjacent sequences: A231261 A231262 A231263 * A231265 A231266 A231267

Keyword

nonn

Author

R. H. Hardin, Nov 06 2013

Status

approved