A202132 Number of zero-sum nX3 -3..3 arrays with every element equal to at least one horizontal or vertical neighbor

1, 123, 1857, 135315, 3767643, 227460779, 8550543057, 461409633685, 19953260512267, 1020672385339045, 47169124107393747, 2357295503312609943, 112529204189556106109, 5573350513364442367517, 270509318554502643186297

Offset

1,2

Comments

Column 3 of A202134

Links

Table of n, a(n) for n=1..15.

Example

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

Crossrefs

Sequence in context: A324627 A259907 A115983 * A160040 A297524 A163711

Adjacent sequences: A202129 A202130 A202131 * A202133 A202134 A202135

Keyword

nonn

Author

R. H. Hardin Dec 11 2011

Status

approved