A208171 Number of nX4 0..3 arrays with new values 0..3 introduced in row major order and no element equal to more than one of its immediate leftward or upward neighbors

15, 2277, 473928, 99752346, 21002874867, 4422202024212, 931104734002155, 196046229442844736, 41277981610623482478, 8691173355900504027213, 1829946411015625966726620, 385299398603702723040648261

Offset

1,1

Comments

Column 4 of A208175

Links

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

Formula

Empirical: a(n) = 226*a(n-1) -3345*a(n-2) +19752*a(n-3) -60897*a(n-4) +108504*a(n-5) -114399*a(n-6) +68040*a(n-7) -18225*a(n-8) for n>9

Example

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

Crossrefs

Sequence in context: A232196 A222881 A229844 * A266571 A308389 A278410

Adjacent sequences: A208168 A208169 A208170 * A208172 A208173 A208174

Keyword

nonn

Author

R. H. Hardin Feb 24 2012

Status

approved