A221733 Number of nX4 arrays of occupancy after each element stays put or moves to some horizontal or antidiagonal neighbor, without move-in move-out left turns

21, 1347, 89920, 5962648, 394328064, 26082119800, 1725138005232, 114104918937179, 7547183523011758, 499189511916458843, 33017637367931117507, 2183868753937529833974, 144446517516157120963359

Offset

1,1

Comments

Column 4 of A221736

Links

R. H. Hardin, Table of n, a(n) for n = 1..103

Formula

Empirical: a(n) = 65*a(n-1) +82*a(n-2) -286*a(n-3) -9015*a(n-4) -13638*a(n-5) -20531*a(n-6) -4247*a(n-7) -4296*a(n-8) +12223*a(n-9) +1713*a(n-10) -233*a(n-11) +12*a(n-12) for n>13

Example

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

Crossrefs

Sequence in context: A268096 A281432 A231782 * A298851 A118446 A130332

Adjacent sequences: A221730 A221731 A221732 * A221734 A221735 A221736

Keyword

nonn

Author

R. H. Hardin Jan 22 2013

Status

approved