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A077902
Expansion of (1-x)^(-1)/(1 + x - x^2 + x^3).
2
1, 0, 2, -2, 5, -8, 16, -28, 53, -96, 178, -326, 601, -1104, 2032, -3736, 6873, -12640, 23250, -42762, 78653, -144664, 266080, -489396, 900141, -1655616, 3045154, -5600910, 10301681, -18947744, 34850336, -64099760, 117897841, -216847936, 398845538, -733591314, 1349284789, -2481721640
OFFSET
0,3
MATHEMATICA
a=0; b=0; c=0; lst={}; Do[z=a+b+c+1; AppendTo[lst, z]; a=b; b=c; c=z; z=a+b+c-1; AppendTo[lst, z]; a=b; b=c; c=z, {n, 5!}]; lst(*Abs values*) (* Vladimir Joseph Stephan Orlovsky, Feb 17 2010 *)
PROG
(PARI) Vec((1-x)^(-1)/(1+x-x^2+x^3)+O(x^99)) \\ Charles R Greathouse IV, Sep 26 2012
CROSSREFS
Sequence in context: A377628 A006367 A246807 * A005834 A367717 A052531
KEYWORD
sign,easy
AUTHOR
N. J. A. Sloane, Nov 17 2002
STATUS
approved