A221359 Number of nX4 arrays of occupancy after each element moves to some horizontal, vertical or antidiagonal neighbor, with no 2-loops and with no occupancy greater than 2

0, 292, 18738, 1388784, 93433746, 6308646549, 423812250312, 28479671473807, 1913505400121105, 128574419200721801, 8639424408948675486, 580522160326792409378, 39007927353168721454490, 2621116666944612733670859

Offset

1,2

Comments

Column 4 of A221361

Links

R. H. Hardin, Table of n, a(n) for n = 1..50

Example

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

Crossrefs

Sequence in context: A221480 A231650 A249239 * A248454 A221832 A238321

Adjacent sequences: A221356 A221357 A221358 * A221360 A221361 A221362

Keyword

nonn

Author

R. H. Hardin Jan 12 2013

Status

approved