A220543 Equals one maps: number of nX3 binary arrays indicating the locations of corresponding elements equal to exactly one of their horizontal and vertical neighbors in a random 0..2 nX3 array

4, 38, 395, 3778, 32126, 261042, 2095121, 16773300, 134209760, 1073726672, 8589906710, 68719426436, 549755721410, 4398046339192, 35184371768852, 281474976122716, 2251799812612122, 18014398507523968, 144115188072265072

Offset

1,1

Comments

Column 3 of A220545

Links

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

Formula

Empirical: a(n) = 8*a(n-1) +3*a(n-2) -24*a(n-3) -2*a(n-4) +24*a(n-5) -60*a(n-6) -44*a(n-7) +91*a(n-8) +40*a(n-9) -3*a(n-10) +28*a(n-11) -28*a(n-12) -32*a(n-13) for n>32

Example

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

Crossrefs

Sequence in context: A220807 A221021 A155859 * A220748 A192947 A234463

Adjacent sequences: A220540 A220541 A220542 * A220544 A220545 A220546

Keyword

nonn

Author

R. H. Hardin Dec 15 2012

Status

approved