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A202026
Number of n X n zero-sum -1..1 arrays with rows and columns lexicographically nondecreasing
0
1, 7, 181, 29363, 29859761, 197324899476, 8770728360813539
OFFSET
1,2
COMMENTS
Diagonal of A202033
EXAMPLE
Some solutions for n=4
.-1.-1.-1..0...-1.-1..0..0...-1.-1.-1..1...-1.-1..1..1...-1..0..1..1
.-1.-1..0..1...-1..1.-1..1...-1..0..1..0...-1.-1..1..1....0..0..0..0
..0..1..1.-1....1.-1.-1..1....0.-1..1..0...-1..1..0..1....0..1.-1..1
..0..1..1..1....1..0..1..0....0..0..1..1....0.-1..0..0....1.-1.-1.-1
CROSSREFS
Sequence in context: A212944 A068339 A219404 * A302904 A059382 A158620
KEYWORD
nonn
AUTHOR
R. H. Hardin Dec 09 2011
STATUS
approved