A267023 Number of 4Xn arrays containing n copies of 0..4-1 with every element equal to or 1 greater than any northeast or northwest neighbors modulo 4 and the upper left element equal to 0.

6, 8, 21, 137, 759, 4835, 31591, 216460, 1516047, 10864196, 79437844, 590119523, 4453596825, 34028591249, 263304258843, 2058154419091, 16252842542358, 129434331448080, 1039407597863960, 8405943746368118, 68447035142972923

Offset

1,1

Comments

Row 4 of A267019.

Links

R. H. Hardin, Table of n, a(n) for n = 1..23

Example

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

Crossrefs

Cf. A267019.

Sequence in context: A306379 A243932 A242504 * A084962 A365649 A296354

Adjacent sequences: A267020 A267021 A267022 * A267024 A267025 A267026

Keyword

nonn

Author

R. H. Hardin, Jan 09 2016

Status

approved