Background: Hydrogen has three naturally occurring isotopes, denoted 1H, 2H and 3H. Other, highly unstable nuclei (4H to 7H) have been synthesized in the laboratory but not observed in nature.
Question: What are the names of these isotopes?
Answer:<extra_id_0>.
<extra_id_0> denoted 1H, 2H and 3H<extra_id_1>