A202031 Number of nX6 zero-sum -1..1 arrays with rows and columns lexicographically nondecreasing

4, 281, 44300, 8249505, 1387552127, 197324899476, 23770010642604, 2467219447235558, 224555987749683857, 18190414439380817926, 1327557199228235157815, 88165919561636605868645

Offset

1,1

Comments

Column 6 of A202033

Links

R. H. Hardin, Table of n, a(n) for n = 1..20

Example

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

Crossrefs

Sequence in context: A134786 A290225 A190635 * A074309 A113256 A259495

Adjacent sequences: A202028 A202029 A202030 * A202032 A202033 A202034

Keyword

nonn

Author

R. H. Hardin Dec 09 2011

Status

approved