Let f(x)=∑n=0∞anxnf(x) = \sum_{n=0}^{\infty} a_n x^nf(x)=∑n=0∞anxn satisfy the differential equation f′(x)=2f(x)f'(x) = 2f(x)f′(x)=2f(x) with initial condition f(0)=3f(0) = 3f(0)=3. What is a2a_2a2?
222
333
666
32\frac{3}{2}23