OFFSET
0,2
COMMENTS
Signed version of A087206.
LINKS
FORMULA
MATHEMATICA
LinearRecurrence[{-2, 4}, {1, -4}, 30] (* Harvey P. Dale, Feb 13 2023 *)
PROG
(PARI) Vec((1-2*x)/(1+2*x-4*x^2)+O(x^99)) \\ Charles R Greathouse IV, Jan 11 2012
CROSSREFS
KEYWORD
sign,easy
AUTHOR
Philippe Deléham, Nov 27 2008
STATUS
approved