A007120 Expansion of e.g.f. (1+x)^(1-x).

1, 1, -2, -3, 16, -10, -114, 462, -496, -2952, 16920, -31680, -130008, 1707576, -14259504, 138375720, -1652311680, 22238105280, -321916019904, 4959460972224, -81123831838080, 1405677742882560, -25732182778727040, 496324987642915200, -10061966722201900416

Offset: 0

Author

Simon Plouffe

Keywords

• sign

References

• N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Links

• Seiichi Manyama, Table of n, a(n) for n = 0..453

Crossrefs

Cf. A005727.

Programs

PARI

a(n) = n!*polcoef((1+x+x*O(x^n))^(1-x), n); \\ Seiichi Manyama, Sep 13 2021

Extensions

Signs from Christian G. Bower, Nov 15 1998

Signs corrected by Sean A. Irvine, Oct 17 2017