Light bulb illumination riddle?

Consider the number of illumination levels available in a floor lamp having the following features. Light is provided by one large, central bulb together with three smaller bulbs clustered around the main stem. The central bulb can shine with 50, 100, or 150 watts, depending on its switch setting. A second switch rotates among four settings: 1 illuminating a single outer bulb, the next powering instead the other 2 smaller bulbs, and the third lighting up all 3 outer bulbs. Suppose each of the 3 smaller bulbs are 60 watts. Find the number of illumination levels possible when the lamp is lit.