A recurrence with complex roots is defined by $a_n = 2a_{n-1} - 2a_{n-2}$ with $a_0 = 0, a_1 = 1$. The characteristic equation $r^2 - 2r + 2 = 0$ has roots $r = 1 \pm i$. In polar form, $r = \sqrt{2} e^{\pm i\pi/4}$. Using Euler's formula, the closed form is $a_n = (\sqrt{2})^n \sin(n\pi/4)$. What is the absolute value of $a_6$?