A006547 Sum ((-1)^(i+1)*binomial(n,i)*2^i*(2*i-1)!,i=1..n).

0, 2, -20, 894, -76936, 11218330, -2486192988, 779417002070, -328459055125136, 179127562413460914, -122758432482044667940, 103274000340320165525422, -104642430930574639703548440, 125699390463431456337149276234

Offset

0,2

Links

Table of n, a(n) for n=0..13.

Mathematica

Table[Sum[(-1)^(i+1) Binomial[n, i]2^i (2i-1)!, {i, n}], {n, 0, 20}] (* Harvey P. Dale, Oct 13 2011 *)

Crossrefs

Sequence in context: A193483 A013148 A276892 * A290883 A135757 A301945

Adjacent sequences: A006544 A006545 A006546 * A006548 A006549 A006550

Keyword

sign

Author

N. J. A. Sloane.

Status

approved