A127235 a(n) = n! (2*sum(1..n-1))!.

1, 4, 4320, 11496038400, 291948240981196800000, 190982059064777562218142105600000000, 7081230833474514688657438735472338312479375360000000000

Offset

1,2

Comments

Number of distinct n x n matrices containing n^2 different elements which have that same trace.

Links

Table of n, a(n) for n=1..7.

Mathematica

Table[n! (2*Sum[x, {x, 1, n - 1}])!, {n, 1, 10}]

Crossrefs

Cf. A127233, A127234.

Sequence in context: A067482 A249804 A079682 * A274972 A344670 A344671

Adjacent sequences: A127232 A127233 A127234 * A127236 A127237 A127238

Keyword

nonn

Author

Artur Jasinski, Jan 09 2007, Jan 11 2007

Status

approved