A156503 Number of n X n arrays of squares of integers, symmetric about main diagonal, with all rows summing to 40.

2, 6, 60, 2914, 1216320, 1982323016, 10802428568204, 144294430454318540

Offset

2,1

Links

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

Crossrefs

Sequence in context: A084971 A224883 A001577 * A077175 A139771 A129665

Adjacent sequences: A156500 A156501 A156502 * A156504 A156505 A156506

Keyword

nonn

Author

R. H. Hardin Feb 09 2009

Status

approved