OFFSET
0,4
LINKS
FORMULA
G.f.: (1-x-4x^2)/((1+2x)(1-2x-x^2)). - R. J. Mathar, Feb 07 2009
MATHEMATICA
LinearRecurrence[{0, 5, 2}, {1, -1, 1}, 35] (* Paolo Xausa, Jan 29 2024 *)
CoefficientList[Series[(1 - x - 4 x^2)/((1 + 2 x) (1 - 2 x - x^2)), {x, 0, 40}], x] (* Wesley Ivan Hurt, Feb 22 2025 *)
CROSSREFS
KEYWORD
sign,easy,changed
AUTHOR
Paul Curtz, Mar 02 2008
EXTENSIONS
More terms from R. J. Mathar, Feb 07 2009
a(30)-a(31) from Paolo Xausa, Jan 29 2024
STATUS
approved