A119836 Bi-diagonal inverse of [k<=n]*n!/(2k)!.

1, -2, 2, 0, -24, 12, 0, 0, -360, 120, 0, 0, 0, -6720, 1680, 0, 0, 0, 0, -151200, 30240, 0, 0, 0, 0, 0, -3991680, 665280, 0, 0, 0, 0, 0, 0, -121080960, 17297280, 0, 0, 0, 0, 0, 0, 0, -4151347200, 518918400, 0, 0, 0, 0, 0, 0, 0, 0, -158789030400, 17643225600, 0, 0, 0, 0, 0, 0, 0, 0, 0, -6704425728000, 670442572800

Offset

0,2

Comments

Row sums are A119837. T(n,n)=A001813(n). T(n,n-1)=2*A001814(n)

Links

Table of n, a(n) for n=0..65.

Formula

Triangle T(n,n)=(2n)!/n!,T(n,n-1)=(2n)!/(n-1)!,T(n,k)=0 otherwise.

Example

Triangle begins
1,
-2, 2,
0, -24, 12,
0, 0, -360, 120,
0, 0, 0, -6720, 1680,
0, 0, 0, 0, -151200, 30240,
0, 0, 0, 0, 0, -3991680, 665280,
0, 0, 0, 0, 0, 0, -121080960, 17297280,
0, 0, 0, 0, 0, 0, 0, -4151347200, 518918400,
0, 0, 0, 0, 0, 0, 0, 0, -158789030400, 17643225600,
0, 0, 0, 0, 0, 0, 0, 0, 0, -6704425728000, 670442572800

Crossrefs

Sequence in context: A069521 A245687 A228617 * A158112 A219496 A163534

Adjacent sequences: A119833 A119834 A119835 * A119837 A119838 A119839

Keyword

easy,sign,tabl

Author

Paul Barry, May 25 2006

Status

approved