

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


1



15, 2277, 473928, 99752346, 21002874867, 4422202024212, 931104734002155, 196046229442844736, 41277981610623482478, 8691173355900504027213, 1829946411015625966726620, 385299398603702723040648261
(list;
graph;
refs;
listen;
history;
text;
internal format)



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(n1) 3345*a(n2) +19752*a(n3) 60897*a(n4) +108504*a(n5) 114399*a(n6) +68040*a(n7) 18225*a(n8) 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



