Você parece estar descrevendo Voyage from Yesteryear de James P. Hogan, como descrito anteriormente em esta resposta
The team, led by Henry B. Congreve, change their mission priority and quickly modify the design to carry several hundred sets of electronically coded human genetic data. Also included in this mission of embryo space colonization is a databank of human knowledge, robots to convert the data into genetic material, care for the children and construct habitats when the destination is reached and a number of artificial wombs. The probe's designers name it the Kuan-Yin after the bodhisattva of childbirth and compassion.
Shortly after the launch, global war indeed breaks out and several decades later, Earthbound humanity is united under an authoritarian government. It is this government that receives a radio message from the fledgling "Chironian" civilization revealing that the probe found a habitable planet (Chiron) and that the first generation of children have been raised successfully.
As the surviving power blocs of Earth before the conflict are still evident, North America, Europe and Asia each send a generation ship to Alpha Centauri to take control of the colony. By the time that the first generation ship (the American Mayflower II) arrives after 20 years, Chironian society is in its fifth generation