A192551 a(n) = sum(abs(stirling1(n+1,k+1))*k!^2,k=0..n)

1, 2, 9, 77, 1150, 27394, 957040, 45996880, 2904500048, 232935169536, 23114775120624, 2779720331819760, 398266855573740192, 67024510463455711776, 13090037070947651891136, 2936252114196522165716544, 749684382637966175707918848

Offset

0,2

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..200

Formula

a(n) ~ sqrt(e)*(n!)^2. - Vaclav Kotesovec, Jan 02 2013

Mathematica

Table[Sum[Abs[StirlingS1[n+1, k+1]]k!^2, {k, 0, n}], {n, 0, 100}]

Prog

(Maxima) makelist(sum(abs(stirling1(n+1, k+1))*k!^2, k, 0, n), n, 0, 24);

Crossrefs

Sequence in context: A277406 A182947 A006041 * A121131 A166891 A184894

Adjacent sequences: A192548 A192549 A192550 * A192552 A192553 A192554

Keyword

nonn

Author

Emanuele Munarini, Jul 04 2011

Status

approved