A210329 1/4 the number of (n+1)X3 0..3 arrays with every 2X2 subblock having two or three distinct clockwise edge differences

406, 11877, 344659, 10050240, 293095459, 8549740834, 249408131339, 7275728429567, 212248230477148, 6191735605717011, 180626272896775892, 5269258543534397671, 153715660936507360882, 4484218150761298939517

Offset

1,1

Comments

Column 2 of A210335

Links

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

Formula

Empirical: a(n) = 47*a(n-1) -547*a(n-2) -255*a(n-3) +35216*a(n-4) -129394*a(n-5) -465060*a(n-6) +2920628*a(n-7) +320982*a(n-8) -20531472*a(n-9) +17232541*a(n-10) +55329403*a(n-11) -75077657*a(n-12) -49764339*a(n-13) +111287472*a(n-14) -12747232*a(n-15) -52250238*a(n-16) +26800488*a(n-17) -2501204*a(n-18) -451078*a(n-19) -5036*a(n-20)

Example

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

Crossrefs

Sequence in context: A203710 A251096 A233052 * A317982 A203936 A172891

Adjacent sequences: A210326 A210327 A210328 * A210330 A210331 A210332

Keyword

nonn

Author

R. H. Hardin Mar 20 2012

Status

approved