%I #23 Jun 13 2015 00:50:48

%S 1,-1,2,-3,6,-10,18,-31,55,-96,169,-296,520,-912,1601,-2809,4930,

%T -8651,15182,-26642,46754,-82047,143983,-252672,443409,-778128,

%U 1365520,-2396320,4205249,-7379697,12950466,-22726483,39882198,-69988378,122821042,-215535903,378239143,-663763424

%N Expansion of (1-x)^(-1)/(1+2*x+x^2+x^3).

%C Signed version of A060945: a(n) = (-1)^n * A060945(n).

%H <a href="/index/Rec">Index entries for linear recurrences with constant coefficients</a>, signature (-1,1,0,1).

%F a(n+1)-a(n) = (-1)^(n+1)*A005314(n+2). - R. J. Mathar, Mar 14 2011

%F a(0)=1, a(1)=-1, a(2)=2, a(3)=-3, a(n)=-a(n-1)+a(n-2)+a(n-4). - _Harvey P. Dale_, Feb 20 2013

%t CoefficientList[Series[1/(1-x)/(1+2x+x^2+x^3),{x,0,50}],x] (* or *) LinearRecurrence[ {-1,1,0,1},{1,-1,2,-3},50] (* _Harvey P. Dale_, Feb 20 2013 *)

%o (PARI) Vec((1-x)^(-1)/(1+2*x+x^2+x^3)+O(x^99)) \\ _Charles R Greathouse IV_, Sep 24 2012

%Y All of A060945, A077930, A181532 are variations of the same sequence. - _N. J. A. Sloane_, Mar 04 2012

%K sign,easy

%O 0,3

%A _N. J. A. Sloane_, Nov 17 2002