An AI model from Anthropic has successfully reproduced five of the ten complex mathematical proofs recently solved by OpenAI's unreleased Astra model, demonstrating that a rival system can match the new reasoning capabilities of its competitor. The available Claude Fable model solved half of theproblems—which had remained open for over a decade—using a generic prompt and independent logical arguments for four of the five cases.

OpenAI's Astra system achieved its original breakthroughs with a total inference cost of approximately $2,000, marking a significant leap in AI scientific reasoning. The replication by an Anthropic researcher without internet access or access to the Astra solutions suggests that advanced mathematical capabilities are converging quickly across the industry's leading frontier models.