FrontierMath Tier 4: what changed — Artificialshttps://artificials.net/tests/frontiermath-tier-4Each new leader on FrontierMath Tier 4.enGPT-6.1 Sol took the top spot on FrontierMath Tier 4 at 100.0%, from GPT-6 Astrahttps://artificials.net/models/gpt-6-1-solleader:2026-10-01:gpt-6-1-sol:frontiermath-tier-4Thu, 01 Oct 2026 00:00:00 GMT