A156442 Number of n X n arrays of squares of integers, symmetric under 90 degree rotation, with all rows summing to 6.

2, 0, 7, 0, 870, 0, 68180, 0, 18391220, 0, 10399874310, 0, 10075020851140, 0, 14707103186511120, 0

Offset

4,1

Links

Table of n, a(n) for n=4..19.

Crossrefs

Sequence in context: A266220 A022897 A192496 * A268683 A174968 A254445

Adjacent sequences: A156439 A156440 A156441 * A156443 A156444 A156445

Keyword

nonn

Author

R. H. Hardin Feb 09 2009

Status

approved