A208391 Number of nX7 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 right-upward antidiagonal neighbors

365, 667476, 1233536544, 2278687944204, 4209452449879284, 7776176148498498768, 14365030966055594634024, 26536707847376158191040692, 49021604272173916567275685956, 90558244799577286285888604547504

Offset

1,1

Comments

Column 7 of A208392

Links

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

Formula

Empirical: a(n) = 1899*a(n-1) -96485*a(n-2) +1863135*a(n-3) -19545624*a(n-4) +128977488*a(n-5) -573780996*a(n-6) +1774673712*a(n-7) -3625252848*a(n-8) +3358392192*a(n-9) +1063196928*a(n-10) for n>12

Example

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

Crossrefs

Sequence in context: A199654 A241113 A208321 * A208398 A258485 A073305

Adjacent sequences: A208388 A208389 A208390 * A208392 A208393 A208394

Keyword

nonn

Author

R. H. Hardin Feb 25 2012

Status

approved