A205164 Number of (n+1) X 3 0..3 arrays with every 2 X 2 subblock having unequal diagonal elements or unequal antidiagonal elements, and new values 0..3 introduced in row major order.

159, 8479, 474853, 26702419, 1502057181, 84495589507, 4753161432989, 267381383420963, 15041106058843389, 846113027177563139, 47596716094317460573, 2677476070233122179939, 150617073927319718240061

Offset

1,1

Comments

Column 2 of A205170.

Links

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

Formula

Empirical: a(n) = 62*a(n-1) -329*a(n-2) +324*a(n-3) -84*a(n-4).

Empirical g.f.: x*(159 - 1379*x + 1466*x^2 - 392*x^3) / ((1 - 5*x + 2*x^2)*(1 - 57*x + 42*x^2)). - Colin Barker, Jun 11 2018

Example

Some solutions for n=4:
..0..1..0....0..1..1....0..0..0....0..0..0....0..0..0....0..0..1....0..0..0
..0..1..0....0..2..1....0..1..1....0..1..0....0..1..1....0..1..1....0..1..1
..0..1..0....1..1..0....2..0..2....2..2..1....1..1..0....2..2..1....2..3..2
..0..1..1....3..2..3....2..1..0....1..3..2....0..0..2....0..3..1....3..1..1
..0..0..0....3..0..0....3..2..2....0..1..0....0..1..2....0..1..0....1..0..3

Crossrefs

Cf. A205170.

Sequence in context: A121804 A293920 A281336 * A221011 A267964 A268029

Adjacent sequences: A205161 A205162 A205163 * A205165 A205166 A205167

Keyword

nonn

Author

R. H. Hardin, Jan 22 2012

Status

approved