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A007120
Expansion of e.g.f. (1+x)^(1-x).
(Formerly M0915)
6
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
0,3
REFERENCES
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
LINKS
PROG
(PARI) a(n) = n!*polcoef((1+x+x*O(x^n))^(1-x), n); \\ Seiichi Manyama, Sep 13 2021
CROSSREFS
Cf. A005727.
Sequence in context: A363920 A074270 A254522 * A092973 A126007 A337111
KEYWORD
sign
AUTHOR
EXTENSIONS
Signs from Christian G. Bower, Nov 15 1998
Signs corrected by Sean A. Irvine, Oct 17 2017
STATUS
approved