OFFSET
0,3
COMMENTS
We can build an auxiliary b(n)=a(n+1)-2a(n) = -1,2,-6,7,..., its bisection b(2n)=a(2n+2)-2a(2n), then take the first differences b(2n+2)-b(2n) = a(2n+4)-3*a(2n+2)+2*a(2n) = -5, -10, -25, -65 and have obtained -A106729(n).
FORMULA
a(n)=4*a(n-2)-4*(n-4)+a(n-6). G.f.: (1+x-2x^3-x^4+2x^5)/((1-x)(1+x)(x^2+x-1)(x^2-x-1)). [R. J. Mathar, Jan 23 2009]
CROSSREFS
KEYWORD
nonn
AUTHOR
Paul Curtz, Jan 14 2009
EXTENSIONS
Edited and extended by R. J. Mathar, Jan 23 2009
STATUS
approved