A156509 Number of n X n arrays of squares of integers, symmetric about main diagonal, with all rows summing to 45.

2, 12, 390, 12963, 1881506, 1336889688, 9293294524192, 249490585063875516

Offset

2,1

Links

Table of n, a(n) for n=2..9.

Crossrefs

Sequence in context: A012547 A009706 A012551 * A229919 A287679 A051009

Adjacent sequences: A156506 A156507 A156508 * A156510 A156511 A156512

Keyword

nonn

Author

R. H. Hardin Feb 09 2009

Status

approved