OFFSET
0,7
LINKS
Harvey P. Dale, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (1,0,-2,2).
FORMULA
a(0)=1, a(1)=1, a(2)=1, a(3)=-1, a(n)=a(n-1)-2*a(n-3)+2*a (n-4). - Harvey P. Dale, Apr 30 2016
MATHEMATICA
CoefficientList[Series[(1-x)^(-1)/(1+2x^3), {x, 0, 60}], x] (* or *) LinearRecurrence[{1, 0, -2, 2}, {1, 1, 1, -1}, 60] (* Harvey P. Dale, Apr 30 2016 *)
PROG
(PARI) a(n)=([0, 1, 0, 0; 0, 0, 1, 0; 0, 0, 0, 1; 2, -2, 0, 1]^n*[1; 1; 1; -1])[1, 1] \\ Charles R Greathouse IV, Oct 03 2016
CROSSREFS
KEYWORD
sign,easy
AUTHOR
N. J. A. Sloane, Nov 17 2002
STATUS
approved