A201888 T(n,k)=Number of zero-sum nXk -2..2 arrays with every element equal to at least one horizontal or vertical neighbor

0, 1, 1, 1, 9, 1, 5, 63, 63, 5, 1, 413, 765, 413, 1, 23, 3293, 26003, 26003, 3293, 23, 25, 25123, 559115, 2171313, 559115, 25123, 25, 97, 196811, 16513425, 184247585, 184247585, 16513425, 196811, 97, 155, 1610765, 435630965, 16910703303

Offset

1,5

Comments

Table starts

..0......1........1.........5.........1..........23........25......97.155

..1......9.......63.......413......3293.......25123....196811.1610765

..1.....63......765.....26003....559115....16513425.435630965

..5....413....26003...2171313.184247585.16910703303

..1...3293...559115.184247585

.23..25123.16513425

.25.196811

.97

Links

Table of n, a(n) for n=1..40.

Example

Some solutions for n=4 k=3
..0..0..0....0..0..2...-2.-2.-2....2..0..0...-2..0..1....2..2..2...-2..0..0
..0..0..0....0..0..2...-2.-2..1....2.-2..0...-2..0..1....2.-1.-1...-2.-1.-1
..2..2.-2....1.-1.-2....1..1..1....1.-2.-2....2..2.-1....0.-1.-1....1..2..0
..2.-2.-2....1.-1.-2....2..2..2....1..0..0....0..0.-1....0.-2.-2....1..2..0

Crossrefs

Sequence in context: A006752 A271856 A164802 * A185825 A198879 A161321

Adjacent sequences: A201885 A201886 A201887 * A201889 A201890 A201891

Keyword

nonn,tabl

Author

R. H. Hardin Dec 06 2011

Status

approved