OFFSET
0,1
COMMENTS
The denominators are A038500(n+1), n >= 0.
This gives one half of the numerators of the z-sequence for the generalized unsigned Lah number Sheffer matrix Lah[3,2] = A290598.
For Sheffer a- and z-sequences see a W. Lang link under A006232 with the references for the Riordan case, and also the present link for a proof.
LINKS
FORMULA
EXAMPLE
The rationals z(3,2;n) = 2*a(n)/A038500(n+1) begin:
{4, -2, 28/3, -70, 728, -29120/3, 158080, -3043040, 608608000/9, -1704102400, 48024704000, -4490309824000/3, ...}
CROSSREFS
KEYWORD
sign,easy
AUTHOR
Wolfdieter Lang, Sep 13 2017
STATUS
approved