A209710 1/4 the number of (n+1)X3 0..3 arrays with every 2X2 subblock having distinct clockwise edge differences

175, 2710, 40600, 614935, 9278940, 140274002, 2118517533, 32012611741, 483591817235, 7306527081148, 110382673709151, 1667687996584917, 25195038977801100, 380647562549584423, 5750778390043860484

Offset

1,1

Comments

Column 2 of A209716

Links

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

Formula

Empirical: a(n) = 9*a(n-1) +155*a(n-2) -718*a(n-3) -5017*a(n-4) +21111*a(n-5) +51148*a(n-6) -251141*a(n-7) -85963*a(n-8) +1092718*a(n-9) -438881*a(n-10) -1923975*a(n-11) +1461077*a(n-12) +1300250*a(n-13) -1385402*a(n-14) -184926*a(n-15) +434126*a(n-16) -73408*a(n-17) -12888*a(n-18) +1440*a(n-19)

Example

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

Crossrefs

Sequence in context: A186212 A355713 A222774 * A056935 A239429 A268872

Adjacent sequences: A209707 A209708 A209709 * A209711 A209712 A209713

Keyword

nonn

Author

R. H. Hardin Mar 11 2012

Status

approved