A202046 Number of zero-sum nX7 -1..1 arrays with every element unequal to at most two horizontal and vertical neighbors

393, 37311, 1067983, 49553277, 2229078023, 108356007319

Offset

1,1

Comments

Column 7 of A202047

Links

Table of n, a(n) for n=1..6.

Example

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

Crossrefs

Sequence in context: A201815 A201554 A172636 * A172737 A172813 A172872

Adjacent sequences: A202043 A202044 A202045 * A202047 A202048 A202049

Keyword

nonn

Author

R. H. Hardin Dec 10 2011

Status

approved