A266995 Number of 3Xn arrays containing n copies of 0..3-1 with no element 1 greater than its west, northeast or northwest neighbor modulo 3 and the upper left element equal to 0.

2, 2, 2, 2, 2, 5, 14, 44, 127, 325, 779, 1794, 3988, 8830, 19835, 45596, 108019, 262831, 649761, 1616713, 4017231, 9918784, 24298996, 59106476, 143053467, 345488183, 834978807, 2023884377, 4926308772, 12044390597, 29559301172, 72735281709

Offset

1,1

Comments

Row 3 of A266994.

Links

R. H. Hardin, Table of n, a(n) for n = 1..106

Example

Some solutions for n=7
..0..2..1..0..2..1..0....0..0..0..0..2..2..1....0..0..0..2..2..1..1
..1..0..2..1..0..2..1....0..0..2..2..2..1..1....0..2..2..2..1..1..0
..2..1..0..2..1..0..2....0..2..2..1..1..1..1....2..2..1..1..1..0..0

Crossrefs

Cf. A266994.

Sequence in context: A115101 A241148 A172414 * A051887 A139516 A225953

Adjacent sequences: A266992 A266993 A266994 * A266996 A266997 A266998

Keyword

nonn

Author

R. H. Hardin, Jan 08 2016

Status

approved