A176391 Number of n X n 1..n arrays with row and column sums n(n+1)/2 and no two adjacent elements equal.

1, 2, 12, 1396, 5147608, 14289569180818

Offset

1,2

Links

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

Crossrefs

Sequence in context: A022482 A081701 A069714 * A123743 A111180 A235857

Adjacent sequences: A176388 A176389 A176390 * A176392 A176393 A176394

Keyword

nonn

Author

R. H. Hardin, Apr 16 2010

Status

approved