Methuselah's Children

Methuselahs Children -- 1941 science fiction novel by Robert Heinlein about a conflict between a group of people who seem to have discovered the fountain of youth and the rest of society -- who refuse to believe that the Howard Familes simply chose their ancestors wisely. This is the first appearance of Lazurus Long, who is so old that when he miscalculates his age he's off by a whole century! Also the first appearance for math genius (Libby something?). Hounded from the earth, the Howards hijack a star ship meant for colonization and try to find a better planet to live on. When Mary Sperling joins the natives, Lazurus decides it's time to go back to earth and claim their rights.