A156420 Number of 15 X 15 arrays of squares of integers, symmetric under 90-degree rotation, with all rows summing to n.

1, 0, 0, 30693320, 1890254100, 0, 0, 686163316440, 4354347220860, 0, 0, 141370447642494, 817218706478195, 0, 0

Offset

0,4

Links

Table of n, a(n) for n=0..14.

Crossrefs

Sequence in context: A204346 A263644 A283619 * A252120 A297447 A205272

Adjacent sequences: A156417 A156418 A156419 * A156421 A156422 A156423

Keyword

nonn

Author

R. H. Hardin, Feb 09 2009

Status

approved