A156459 Number of n X n arrays of squares of integers, symmetric about both diagonal and antidiagonal, with all rows summing to 13.

2, 0, 28, 12, 1412, 3096, 337208, 4171320, 662224128, 16504055920, 4410398887272, 150978985010061, 66490911199244672

Offset

2,1

Links

Table of n, a(n) for n=2..14.

Crossrefs

Sequence in context: A327601 A336287 A337074 * A356564 A007218 A092177

Adjacent sequences: A156456 A156457 A156458 * A156460 A156461 A156462

Keyword

nonn

Author

R. H. Hardin Feb 09 2009

Status

approved