login
A231444
Number of (n+1) X (1+1) 0..3 arrays with no element unequal to a strict majority of its horizontal and antidiagonal neighbors, with values 0..3 introduced in row major order.
1
2, 6, 23, 102, 492, 2485, 12858, 67354, 355003, 1876862, 9937840, 52659593, 279141170, 1479959118, 7847200511, 41610135894, 220644482580, 1170015798397, 6204298839786, 32899919832226, 174460671091171, 925125214479854
OFFSET
1,1
LINKS
FORMULA
Empirical: a(n) = 11*a(n-1) - 41*a(n-2) + 65*a(n-3) - 43*a(n-4) + 9*a(n-5).
Empirical g.f.: x*(2 - 16*x + 39*x^2 - 35*x^3 + 9*x^4) / ((1 - x)*(1 - 3*x + x^2)*(1 - 7*x + 9*x^2)). - Colin Barker, Sep 28 2018
EXAMPLE
Some solutions for n=7:
..0..0....0..0....0..0....0..0....0..0....0..0....0..0....0..0....0..0....0..0
..1..1....1..1....1..1....1..1....1..1....1..1....0..1....1..1....1..1....0..1
..1..1....0..0....0..0....2..2....2..2....1..1....1..2....2..2....1..1....1..0
..0..0....2..2....0..0....3..3....3..3....2..2....2..3....1..1....1..2....0..0
..0..2....2..1....1..1....3..3....2..2....2..2....3..3....0..0....2..1....0..0
..2..2....1..1....1..1....0..0....3..3....2..1....0..0....3..3....1..0....0..0
..2..2....1..1....2..2....0..0....1..1....1..3....1..1....3..3....0..0....0..0
..2..2....0..0....3..3....0..0....3..3....3..3....3..3....0..0....3..3....1..1
CROSSREFS
Column 1 of A231451.
Sequence in context: A263576 A370196 A370213 * A248900 A376395 A120346
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 09 2013
STATUS
approved