A232788 A232773(n) / A006882(n): Permanent of the n X n matrix with elements [1,2,...,n^2], divided by n!!.

1, 1, 5, 150, 6932, 965380, 143299890, 51176650000, 16737737386944, 11806879466638656, 7023172771916784000, 8447153882019234307200, 8134080139379917205277696, 15176253254155788712392633600, 21875035292051870323313614135440, 59270306784445546617788929301760000

Offset

0,3

Comments

Limit n->infinity a(n)^(1/n)/n^(5/2) = exp(-3/2). - Vaclav Kotesovec, Nov 08 2014

Links

Alois P. Heinz, Table of n, a(n) for n = 0..100

Maple

with(combinat):
a:= n-> (-1)^n *add(n^k *stirling1(n, n-k)*stirling1(n+1, k+1)
        *(n-k)!* k!, k=0..n)/doublefactorial(n):
seq(a(n), n=0..20);  # Alois P. Heinz, Dec 02 2013

Mathematica

Flatten[{1, Table[(-1)^n*Sum[n^k*StirlingS1[n, n-k]*StirlingS1[n+1, k+1]*(n-k)!*k!, {k, 0, n}]/n!!, {n, 1, 20}]}] (* Vaclav Kotesovec, Nov 08 2014 *)

Prog

(PARI) n->(-1)^n*sum(k=0, n, n^k*stirling(n, n-k)*stirling(n+1, k+1)*(n-k)!*k!)/A006882(n)

Crossrefs

Cf. A232773, A006882.

Sequence in context: A230666 A113560 A094364 * A324097 A082441 A096065

Adjacent sequences: A232785 A232786 A232787 * A232789 A232790 A232791

Keyword

nonn

Author

M. F. Hasler, Nov 30 2013

Extensions

a(0)=1 inserted by Alois P. Heinz, Dec 02 2013

Status

approved