A156456 Number of n X n arrays of squares of integers, symmetric about both diagonal and antidiagonal, with all rows summing to 12.

1, 12, 12, 926, 3066, 417378, 4260776, 624439948, 10607876660, 2165316809841, 59576593947316, 18657442342135966

Offset

3,2

Links

Table of n, a(n) for n=3..14.

Crossrefs

Sequence in context: A221796 A222298 A122253 * A077180 A105745 A020511

Adjacent sequences: A156453 A156454 A156455 * A156457 A156458 A156459

Keyword

nonn

Author

R. H. Hardin Feb 09 2009

Status

approved