We introduce FrontierMath Erdős (FME), a benchmark of 68 Erdős problems that are open as of August 2026. To solve a task in FME, AI systems must resolve (prove or disprove) one of the 68 conjectures in the proof assistant Lean. Our 68 problems were selected by the second author among 652 open problems on erdosproblems.com for their mathematical interest and difficulty. AIs have recently resolved several open problems in mathematics, but these demonstrations fall short of a systematic study of AI capabilities. FME evaluates every AI model on the same fixed problems, autonomously and under the same budget. We evaluated five AIs with a budget of $300 per problem. One (GPT-6 Astra) scored 3%, and all others scored 0%.
Figures & tables
Model
Score
GPT-6 Astra (pre-release)
3%
GPT-5.6 Sol
0%
GPT-5.5
0%
Claude Fable 5.1
0%
Claude Fable 5
0%
Table 1: Benchmark scores in the default configuration: one attempt per conjecture, $300 and 72 hours of working time per attempt. The score is the percentage of the 68 conjectures resolved.
Problem
Cost
Working time
#74
$218
15 h
#126
$247
16 h
Table 2: Cost and working time of the two resolutions in the default configuration.
Table 3: All resolutions by GPT-6 Astra across every attempt, including the non-systematic additional attempts described in the text. Unlike Table 2 , this is not a benchmark result: attempts differ in budget and agent configuration, and conjectures were attempted different numbers of times. “Resolved in” counts attempts that had reached a verdict by the time of writing.
Appendix figures & tables1 asset
Supplementary material from the paper’s appendix.
Appendix
ID
Conjecture
Erdos1
If every subset of A⊆{1,…,N} has a distinct sum, then N≫2∣A∣ .
Erdos3
If A⊆N has ∑n∈A1/n=∞ , then A contains arbitrarily long arithmetic progressions.
Erdos5
Every C≥0 is a limit point of the normalised prime gaps (pn+1−pn)/logn .
Erdos7
There is a covering system of the integers all of whose moduli are odd and greater than 1 .
Erdos20
Sunflower conjecture: the minimal f(n,k) such that every family of f(n,k) many n -element sets contains a k -sunflower satisfies f(n,k)<ckn .
Erdos23
Every triangle-free graph on 5n vertices can be made bipartite by deleting at most n2 edges.
Appendix
Table 4: The 68 conjectures of FrontierMath Erdős.
Recent AI systems have achieved gold-medal-level performance on the International Mathematical Olympiad, demonstrating remarkable proficiency at competition-style problem solving. However, competition mathematics represents only a narrow slice of mathematical reasoning: problems are drawn from limited domains, require minimal advanced machinery, and can often reward insightful tricks over deep theoretical knowledge. We introduce Riemann-Bench, a private benchmark of expert-curated problems designed to evaluate AI systems on research-level mathematics that goes far beyond the olympiad frontier. Problems are authored by Ivy League mathematics professors, graduate students, and PhD-holding IMO medalists, and routinely took their authors weeks to solve independently. Each problem undergoes double-blind verification by two independent domain experts who must solve the problem from scratch, and yields a unique, closed-form solution assessed by programmatic verifiers. We evaluate frontier models as unconstrained research agents, with full access to coding tools, search, and open-ended reasoning, using an unbiased statistical estimator computed over 100 independent runs per problem. Our results reveal that all frontier models currently score below 10%, exposing a substantial gap between olympiad-level problem solving and genuine research-level mathematical reasoning. By keeping the benchmark fully private, we ensure that measured performance reflects authentic mathematical capability rather than memorization of training data.
Can AI make progress on important, unsolved mathematical problems? Large language models are now capable of sophisticated mathematical and scientific reasoning, but whether they can perform novel research is still widely debated and underexplored. We introduce HorizonMath, a benchmark of 113 predominantly unsolved problems spanning eight domains in mathematics and the mathematical sciences, paired with an open-source evaluation framework for automated verification. Our benchmark targets the generator-verifier gap: problems where discovery is hard and requires meaningful mathematical insight, but verification is computationally straightforward. This contrasts with most existing research-level benchmarks, which instead rely on formal proof verification or manual review, both of which are expensive to scale. Because these solutions are unknown, HorizonMath is resistant to data contamination, and most state-of-the-art models score under 10%. Using this framework, we identify six novel solutions to research problems that either resolve previously open questions or improve on the best-known published results, with GPT-5.4 Pro and GPT-5.6 Sol each discovering three of these solutions. Across seven frontier model families, reasoning efficiency and behavior also vary substantially. We release HorizonMath as an open challenge and a growing community resource, where each verified solution is a candidate contribution to the mathematical literature.
Erik Y. Wang, Sumeet R. Motwani, James V. Roggeveen +9
Stanford University · Benchmark · University of Oxford +3
Large language models (LLMs) increasingly excel at mathematical reasoning, but their unreliability limits their utility in mathematics research. A mitigation is using LLMs to generate formal proofs in languages like Lean. We perform the first large-scale evaluation of this method's ability to solve open problems. Our most capable agent autonomously resolved 9 of 353 open Erdős problems at the per-problem cost of a few hundred dollars, proved 44/492 OEIS conjectures, and is being deployed in combinatorics, optimization, graph theory, algebraic geometry, and quantum optics research. A basic agent alternating LLM-based generation with Lean-based verification replicated the Erdős successes but proved costlier on the hardest problems. These findings demonstrate the power of AI-aided formal proof search and shed light on the agent designs that enable it.
George Tsoukalas, Anton Kovsharov, Sergey Shirobokov +18