A267902 Number of 2Xn arrays containing n copies of 0..2-1 with every element equal to at least one horizontal or vertical neighbor and the top left element equal to 0.

0, 2, 3, 11, 29, 93, 268, 842, 2547, 7946, 24539, 76721, 239462, 751569, 2360679, 7437243, 23461543, 74155431, 234687456, 743792675, 2359972537, 7496293462, 23834595755, 75852059135, 241594260984, 770090455545, 2456436981617

Offset

1,2

Comments

Row 2 of A267901.

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Example

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

Crossrefs

Cf. A267901.

Sequence in context: A243896 A202211 A104081 * A003455 A103275 A278209

Adjacent sequences: A267899 A267900 A267901 * A267903 A267904 A267905

Keyword

nonn

Author

R. H. Hardin, Jan 22 2016

Status

approved