A222382 Sum of neighbor maps: number of n X 3 binary arrays indicating the locations of corresponding elements equal to the sum mod 3 of their horizontal and antidiagonal neighbors in a random 0..2 n X 3 array.

8, 48, 512, 3968, 32768, 261376, 2097152, 16773120, 134217728, 1073721344, 8589934592, 68719378432, 549755813888, 4398046052352, 35184372088832, 281474974613504, 2251799813685248, 18014398500044800, 144115188075855872

Offset: 1

Author

R. H. Hardin, Feb 18 2013

Keywords

• nonn

Comments

Column 3 of A222386.

Examples

			Some solutions for n=3:
..1..1..1....1..1..1....0..1..0....1..1..1....0..0..1....0..1..1....0..1..1
..1..1..1....1..1..0....0..1..0....1..0..0....0..1..0....1..0..0....1..0..0
..1..1..0....0..1..1....1..0..0....0..1..1....1..1..1....1..0..1....1..0..0
		

Links

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

Crossrefs

Cf. A222386.

Formula

Empirical: a(n) = 8*a(n-1) + 8*a(n-2) - 64*a(n-3) - 16*a(n-4) + 128*a(n-5).

Empirical g.f.: 8*x*(1 - 2*x + 8*x^2 + 16*x^4) / ((1 - 2*x)^2*(1 + 2*x)^2*(1 - 8*x)). - Colin Barker, Aug 16 2018