What is the closed form of an=2an−1−2an−2a_n = 2a_{n-1} - 2a_{n-2}an=2an−1−2an−2 with a0=0,a1=1a_0=0, a_1=1a0=0,a1=1?
an=(2)nsin(nπ/4)a_n = (\sqrt{2})^n \sin(n\pi/4)an=(2)nsin(nπ/4)
an=2n/2sin(nπ/4)a_n = 2^{n/2} \sin(n\pi/4)an=2n/2sin(nπ/4)
an=sin(nπ/4)a_n = \sin(n\pi/4)an=sin(nπ/4)
an=2ncos(nπ/4)a_n = 2^n \cos(n\pi/4)an=2ncos(nπ/4)