A210150 1/4 the number of (n+1) X 3 0..3 arrays with every 2 X 2 subblock having one, three or four distinct clockwise edge differences.

820, 42689, 2219034, 115368738, 5997955680, 311831135649, 16211961522199, 842852674077118, 43819535708838103, 2278158176293618573, 118440430549650177612, 6157665317047215194813, 320134281687114509018719

Offset

1,1

Comments

Column 2 of A210156.

Links

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

Formula

Empirical: a(n) = 49*a(n-1) +200*a(n-2) -2256*a(n-3) -3750*a(n-4) +29143*a(n-5) -5802*a(n-6) -84658*a(n-7) +57585*a(n-8) +56482*a(n-9) -40584*a(n-10) -14146*a(n-11) +6952*a(n-12) +1280*a(n-13).

Example

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

Crossrefs

Cf. A210156.

Sequence in context: A248996 A043460 A038489 * A230784 A022254 A095964

Adjacent sequences: A210147 A210148 A210149 * A210151 A210152 A210153

Keyword

nonn

Author

R. H. Hardin, Mar 18 2012

Status

approved