A267397 Number of 4Xn arrays containing n copies of 0..4-1 with every element equal to or 1 greater than any north, west or northeast neighbors modulo 4 and the upper left element equal to 0.

1, 2, 5, 12, 36, 127, 491, 1975, 7870, 31298, 124276, 500855, 2061014, 8699937, 37534533, 164436255, 725855629, 3210406564, 14185263492, 62597467436, 276260201275, 1221933146012, 5426950430555, 24226437430604, 108701332822518

Offset

1,2

Comments

Row 4 of A267392.

Links

R. H. Hardin, Table of n, a(n) for n = 1..37

Example

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

Crossrefs

Cf. A267392.

Sequence in context: A323933 A038142 A287427 * A267398 A267399 A267400

Adjacent sequences: A267394 A267395 A267396 * A267398 A267399 A267400

Keyword

nonn

Author

R. H. Hardin, Jan 13 2016

Status

approved