A156448 Number of n X n arrays of squares of integers, symmetric about main diagonal, with all rows summing to 9.

1, 2, 8, 68, 868, 19436, 638012, 57507580, 22620401127, 17074878770018, 18408433074826454

Offset

1,2

Links

Table of n, a(n) for n=1..11.

Crossrefs

Sequence in context: A393837 A394195 A361213 * A262479 A372315 A192550

Adjacent sequences: A156445 A156446 A156447 * A156449 A156450 A156451

Keyword

nonn

Author

R. H. Hardin, Feb 09 2009

Status

approved