@sophiamyang: Introducing Leanstral 1.5 A 119B (6B active) open model for formal proof engineering in Lean 4: 100% on miniF2F 587/672…
Summary
Introducing Leanstral 1.5, a 119B parameter (6B active) open model for formal proof engineering in Lean 4, achieving 100% on miniF2F, state-of-the-art scores on PutnamBench and FATE benchmarks, and discovering previously unknown bugs in open-source repositories.
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Cached at: 07/04/26, 10:46 AM
Introducing Leanstral 1.5 🔬
A 119B (6B active) open model for formal proof engineering in Lean 4:
✅ 100% on miniF2F ✅ 587/672 on PutnamBench (~$4/problem) ✅ SOTA on FATE-H (87%) & FATE-X (34%) ✅ Found 5 previously unknown bugs in real OSS repos
Apache-2.0. Free API. https://t.co/8xIuPwnuI6
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