Suppose we have a staircase with n steps (we start on the ground, so we need n total steps to reach the top). We can take as many steps forward at a time, but we will never step backwards. How many ways are there to reach the top? Give your answer as a function of n. For example: if n = 3, then the answer is 4. The four options are the following: (1) take one step, take one step, take one step (2) take two steps, take one step (3) take one step, take two steps (4) take three steps