There's at least one key common denominator here: tremendous growth prospects.Don't want to think too hard about your investing decisions? Then go with the stocks of highly profitable companies with strong growth prospects.Three Motley Fool contributors identified several stocks that fit this description. Here's why they think Eli Lilly (LLY 2.11%), Novo Nordisk (NVO 1.19%), and Vertex Pharmaceuticals (VRTX 0.52%) are no-brainer healthcare stocks to buy in September.The growth machine that never runs out of ...