OpenAI said Tuesday that one of its unreleased artificial intelligence models had solved a mathematical puzzle that has eluded mathematicians for generations, a claim that also drew a fight with rival researchers over credit.

A mathematician compared the feat to the history-making chess competition in which IBM’s Deep Blue computer beat Garry Kasparov in 1997

South Korean students remained among the world's top performers in digital problem-solving, science and math but posted weaker reading scores.