A077926 Expansion of (1-x)^(-1)/(1+2*x+x^3).
1, -1, 3, -6, 14, -30, 67, -147, 325, -716, 1580, -3484, 7685, -16949, 37383, -82450, 181850, -401082, 884615, -1951079, 4303241, -9491096, 20933272, -46169784, 101830665, -224594601, 495358987, -1092548638, 2409691878, -5314742742, 11722034123, -25853760123, 57022262989, -125766560100
Offset: 0
Links
- Index entries for linear recurrences with constant coefficients, signature (-1,2,-1,1).
Programs
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PARI
Vec((1-x)^(-1)/(1+2*x+x^3)+O(x^99)) \\ Charles R Greathouse IV, Sep 27 2012
Formula
a(n)=-a(n-1)+2*a(n-2)-a(n-3)+a(n-4). - N-E. Fahssi, Mar 29 2008
a(n) -a(n-1) = (-1)^n*A008998(n). - R. J. Mathar, Jun 08 2020