Find the characteristic equation for the recurrence an=2an−1+3an−3a_n = 2a_{n-1} + 3a_{n-3}an=2an−1+3an−3.
r3−2r−3=0r^3 - 2r - 3 = 0r3−2r−3=0
r3−2r2−3=0r^3 - 2r^2 - 3 = 0r3−2r2−3=0
r2−2r−3=0r^2 - 2r - 3 = 0r2−2r−3=0
r3+2r2+3=0r^3 + 2r^2 + 3 = 0r3+2r2+3=0