OFFSET
0,4
LINKS
Index entries for linear recurrences with constant coefficients, signature (0,3,0,-3,0,1).
FORMULA
G.f.: (1-x-4x^2+x^3+x^4)/((1-x)^3*(1+x)^3).
a(n) = 3a(n-2)-3a(n-4)+a(n-6).
a(n) = (6-n^2)(-1)^n/8-(n^2+4n-2)/8.
a(2n) = A110331(n). - R. J. Mathar, Aug 22 2012
CROSSREFS
KEYWORD
easy,sign
AUTHOR
Paul Barry, Jul 19 2005
STATUS
approved