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

Author

R. H. Hardin, Jan 22 2016

Keywords

• nonn

Comments

Row 2 of A267901.

Examples

			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
		

Links

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

Crossrefs

Cf. A267901.