A221738 - OEIS

A221738

Number of 3Xn arrays of occupancy after each element stays put or moves to some horizontal or antidiagonal neighbor, without move-in move-out left turns

1, 91, 2904, 89920, 2756353, 84394752, 2583450288, 79076354944, 2420345277285, 74080136453919, 2267377897799414, 69397723169867694, 2124057415530302013, 65011050835979200659, 1989793867498843870414, 60901638841473991347603

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

COMMENTS

Row 3 of A221736

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..41

EXAMPLE

Some solutions for n=3

..2..0..0....0..1..2....0..3..1....1..1..0....0..1..1....1..2..0....0..2..0

..2..1..1....1..1..0....1..1..0....1..2..1....1..3..0....0..2..2....2..2..0

..0..3..0....1..2..1....2..0..1....1..1..1....2..1..0....1..1..0....0..2..1