Excuse me, but I'm a bit confused about the question. Adderall is a medication used to treat attention deficit hyperactivity disorder (ADHD) and certain other conditions. It's a combination of amphetamine and dextroamphetamine, both of which are stimulant drugs. Now, medications like Adderall typically come in the form of tablets or capsules, and they're not colored in a way that directly corresponds to their dosage strength. So, to ask what color is 20 mg of Adderall doesn't quite make sense, as the color can vary depending on the manufacturer and the specific formulation. Could you perhaps clarify your question, or are you referring to something else entirely?