A156504 Number of n X n arrays of squares of integers, symmetric about both diagonal and antidiagonal, with all rows summing to 40.

2, 0, 32, 114, 16570, 196824, 116949508, 3753914276, 4711859922047

Offset

2,1

Links

Table of n, a(n) for n=2..10.

Crossrefs

Sequence in context: A176726 A156452 A156473 * A395034 A340545 A009665

Adjacent sequences: A156501 A156502 A156503 * A156505 A156506 A156507

Keyword

nonn

Author

R. H. Hardin, Feb 09 2009

Status

approved