A109582 - OEIS

%I #7 Aug 19 2022 14:38:54

%S -1,1,-2,0,24,-240,1440,-5040,-40320,1088640,-14515200,119750400,0,

%T -24908083200,610248038400,-9153720576000,62768369664000,

%U 1422749712384000,-70426110763008000,1703031405723648000,-24329020081766400000,-51090942171709440000

%N Expansion of e.g.f.: -1/(1+x-x^3).

%F E.g.f.: -1/(1+x-x^3).

%F a(n) = n!*A104769(n+1). - _R. J. Mathar_, Aug 20 2021

%F D-finite with recurrence a(n) +n*a(n-1) -n*(n-1)*(n-2)*a(n-3) = 0. - _R. J. Mathar_, Aug 20 2021

%p g:=-1/(1+x-x^3):gser:=series(g,x=0,26): -1,seq(n!*coeff(gser,x^n),n=1..22);

%Y Cf. A050935, A104769.

%K sign

%O 0,3

%A _Roger L. Bagula_, Jun 29 2005