OFFSET
1,5
COMMENTS
Apart from the offset, the same as A077968.
LINKS
G. C. Greubel, Table of n, a(n) for n = 1..1000
Index entries for linear recurrences with constant coefficients, signature (0,-2,-2).
MATHEMATICA
M = {{0, 1, 0}, {0, 0, 1}, {-2, -2, 0}}; v[1] = {0, 0, 1}; v[n_] := v[n] = M.v[n - 1]; a1 = Table[v[n][[1]], {n, 1, 50}]
LinearRecurrence[{0, -2, -2}, {0, 0, 1}, 50] (* G. C. Greubel, Jun 24 2019 *)
PROG
(PARI) my(x='x+O('x^50)); concat([0, 0], Vec( x^3/(1+2*x^2+2*x^3) )) \\ G. C. Greubel, Jun 24 2019
(Magma) R<x>:=PowerSeriesRing(Integers(), 50); [0, 0] cat Coefficients(R!( x^3/(1+2*x^2+2*x^3) )); // G. C. Greubel, Jun 24 2019
(Sage) a=(x^3/(1+2*x^2+2*x^3)).series(x, 50).coefficients(x, sparse=False); a[1:] # G. C. Greubel, Jun 24 2019
(GAP) a:=[0, 0, 1];; for n in [4..50] do a[n]:=-2*(a[n-2]+a[n-3]); od; a; # G. C. Greubel, Jun 24 2019
CROSSREFS
KEYWORD
sign,easy
AUTHOR
Roger L. Bagula and Gary W. Adamson, Oct 27 2006
STATUS
approved