A208320 Number of nX6 0..2 arrays with new values 0..2 introduced in row major order and no element equal to more than two of its immediate leftward or upward or left-upward diagonal neighbors.

122, 74164, 45806048, 28269518640, 17447625342768, 10768439015566880, 6646136838761770080, 4101906889966246046656, 2531642149413205778426624, 1562495723122773848862609024, 964351492313036003827665859200

Offset

1,1

Comments

Column 6 of A208322

Links

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

Formula

Empirical: a(n) = 537*a(n-1) +49592*a(n-2) +31826*a(n-3) -58803472*a(n-4) +179637996*a(n-5) +25002428576*a(n-6) -374089290720*a(n-7) +1673162178864*a(n-8) +1458727001312*a(n-9) -26670663438976*a(n-10) +22320866668800*a(n-11) +163473207070720*a(n-12) -154760782270464*a(n-13) -553868665028608*a(n-14) +195352269029376*a(n-15) +950302465851392*a(n-16) +420741501681664*a(n-17) -139097129615360*a(n-18) -88593968136192*a(n-19) +5745055629312*a(n-20) +4232690270208*a(n-21) for n>22

Example

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

Crossrefs

Sequence in context: A199653 A241112 A240705 * A208390 A282274 A208397

Adjacent sequences: A208317 A208318 A208319 * A208321 A208322 A208323

Keyword

nonn

Author

R. H. Hardin, Feb 25 2012

Status

approved