A130105 a(n)=(2n)!*B_n, B_n=n-th Bernoulli number.

1, -1, 4, 0, -1344, 0, 11404800, 0, -697426329600, 0, 184310758195200000, 0, -157043899486325440512000, 0, 355703068713666170585088000000, 0, -1866165170959155879636916764672000000, 0

Offset

0,3

Comments

a(n)=(2n)!*A027641(n)/A027642(n).

Links

Table of n, a(n) for n=0..17.

Formula

a(n)=(2n)!*sum{k=0..n,(1/(k+1))*sum{j=0..k,(-1)^j*C(k,j)*j^n}};

Crossrefs

Sequence in context: A012688 A216675 A012502 * A013463 A013464 A331582

Adjacent sequences: A130102 A130103 A130104 * A130106 A130107 A130108

Keyword

easy,sign

Author

Paul Barry, May 07 2007

Status

approved