Formal theorem proving enables machine-verifiable evaluation of mathematical reasoning, yet existing benchmarks often emphasize aggregate proof accuracy, concentrate on a narrow range of mathematics, and provide limited evidence of robustness to equivalent reformulations. We introduce MathAdv, a diagnostic benchmark spanning 13 domains across undergraduate- and graduate-level mathematics. Alongside Lean 4 theorem proving, MathAdv provides up to three auxiliary tasks: multiple-choice questions that probe mathematical knowledge, fill-in-the-blank problems that isolate informal reasoning, and expert-crafted transformations that test robustness to problem presentation. Our evaluation of contemporary theorem provers yields four findings: formalization remains a major bottleneck; performance varies substantially across mathematical domains; natural-language guidance helps general-purpose LLMs but can hinder proof-specialized models; and mathematically equivalent reformulations expose substantial robustness limitations. Together, these results show how component-wise evaluation can reveal model capabilities and failure modes that aggregate theorem-proving accuracy obscures. The dataset and evaluation scripts are available at https://github.com/margotyjx/MathAdv.git.
Figures & tables
Figure 1: MathAdv at a glance.
Figure 2: Left: Distribution of the 321 problems across mathematical domains. Right: An original probability problem with its direct-answer and multiple-choice diagnostic tasks.
Figure 3: Human-in-the-loop autoformalization process for MathAdv.
Figure 4Table 5Figure 6
Appendix figures & tables20 assets
Supplementary material from the paper’s appendix.
Appendix
Figure 6: Multiple-choice Reasoning Problems by Category (Total = 293).
Figure 7: Transformed Problems by Category (Total = 30).
Figure 8: Fill-in-the-blank Problems by Category (Total = 81).
Model
Compilation Accuracy (%)
Semantic Understanding (0–2)
gpt-5.5
58%
2.00
deepseek-v4-pro
4%
1.91
deepseek-chat
4%
1.51
gpt-4o
18%
0.89
Appendix
Table 5: Model performance on the Lean 4 Junk Theorems testbed.
Domain
N
DS Non-Int.
DS Int.
DS Δ
GPT Non-Int.
GPT Int.
GPT Δ
Abstract Algebra
30
10.0%
10.0%
+0.0%
16.7%
23.3%
+6.7%
Calculus
26
3.9%
3.9%
+0.0%
7.7%
7.7%
+0.0%
Combinatorial
23
4.3%
4.3%
+0.0%
8.7%
8.7%
+0.0%
Complex Analysis
15
0.0%
0.0%
+0.0%
0.0%
0.0%
+0.0%
Fourier Analysis
31
9.7%
9.7%
+0.0%
9.7%
12.9%
+3.2%
Functional Analysis
25
4.0%
4.0%
+0.0%
4.0%
4.0%
+0.0%
Appendix
Table 6: Lean 4 accuracy by domain with and without interaction.
Domain
Lean 4 Acc. (%)
MC Acc. (%)
Abstract Algebra
0.0
58.3
Calculus
0.0
48.1
Combinatorial
0.0
65.2
Complex Analysis
0.0
43.8
Fourier Analysis
3.2
54.8
Functional Analysis
0.0
48.0
Appendix
Table 7: Accuracy by domain for DeepSeek V1.5 Base.
Domain
Lean 4 Acc. (%)
MC Acc. (%)
Abstract Algebra
16.7
16.7
Calculus
0.0
37.0
Combinatorial
4.3
43.5
Complex Analysis
0.0
37.5
Fourier Analysis
9.7
29.0
Functional Analysis
4.0
32.0
Appendix
Table 8: Accuracy by domain for DeepSeek V1.5 SFT.
Domain
Lean 4 Acc. (%)
MC Acc. (%)
Abstract Algebra
16.7
41.7
Calculus
7.7
18.5
Combinatorial
4.3
52.2
Complex Analysis
0.0
25.0
Fourier Analysis
9.7
22.6
Functional Analysis
4.0
44.0
Appendix
Table 9: Accuracy by domain for DeepSeek V1.5 RL.
Domain
Lean 4 Acc. (%)
MC Acc. (%)
Abstract Algebra
20.0
41.7
Calculus
15.4
29.6
Combinatorial
4.3
30.4
Complex Analysis
0.0
37.5
Fourier Analysis
12.9
48.4
Functional Analysis
4.0
44.0
Appendix
Table 10: Accuracy by domain for RMaxTS.
Domain
Lean 4 Acc. (%)
MC Acc. (%)
Abstract Algebra
23.3
75.0
Calculus
19.2
70.4
Combinatorial
4.3
73.9
Complex Analysis
0.0
68.8
Fourier Analysis
9.7
54.8
Functional Analysis
4.0
60.0
Appendix
Table 11: Accuracy by domain for InternLM2-Math.
Domain
Solved
Total
Lean 4 Acc. (%)
Abstract Algebra
5
30
16.7
Calculus
4
26
15.4
Combinatorial
0
23
0.0
Complex Analysis
0
15
0.0
Fourier Analysis
3
31
9.7
Functional Analysis
1
25
4.0
Appendix
Table 12: Accuracy by domain for InternLM2.5 Step Prover.
Domain
Lean 4 Acc. (%)
MC Acc. (%)
Abstract Algebra
16.7
16.7
Calculus
11.5
22.2
Combinatorial
4.3
26.1
Complex Analysis
0.0
18.8
Fourier Analysis
9.7
12.9
Functional Analysis
4.0
28.0
Appendix
Table 13: Accuracy by domain for Goedel SFT.
Domain
Lean 4 Acc. (%)
MC Acc. (%)
Abstract Algebra
10.0
16.7
Calculus
15.4
22.2
Combinatorial
4.3
26.1
Complex Analysis
0.0
12.5
Fourier Analysis
9.7
16.1
Functional Analysis
8.0
28.0
Appendix
Table 14: Accuracy by domain for Goedel DPO.
Domain
Solved
Total
Lean 4 Acc. (%)
Abstract Algebra
7
30
23.3
Calculus
5
26
19.2
Combinatorial
2
23
8.7
Complex Analysis
1
15
6.7
Fourier Analysis
4
31
12.9
Functional Analysis
1
25
4.0
Appendix
Table 15: Goedel v2 union outcomes aggregated by domain.
Domain
Solved
Total
Lean 4 Acc. (%)
Abstract Algebra
4
30
13.3
Calculus
3
26
11.5
Combinatorial
1
23
4.3
Complex Analysis
3
15
20.0
Fourier Analysis
3
31
9.7
Functional Analysis
1
25
4.0
Appendix
Table 16: Accuracy by domain for MA-LoT + DeepSeek V1.5.
LLMs have recently achieved strong results on formal proving benchmarks. However, existing evaluations remain heavily concentrated on competition-style problems and often fail to capture how models behave on longer, more dependency-rich mathematical developments. We introduce TheoremBench, a Lean4 benchmark designed to evaluate theorem provers beyond contest settings. The benchmark is built from nearly one hundred classical theorems and is released in two complementary forms: a plain main version containing one target theorem per instance, and a premised version that expands each theorem into a structured family of related proving tasks consisting of the main theorem together with automatically extracted supporting subtheorems. This design enables evaluation of not only whether the final theorem was proved from scratch, but also of partial progress through the internal proof structure of a theorem. Our experiments show that explicit premises substantially improve performance for Lean4-capable prover models. To provide a comprehensive evaluation, we introduce theorem-level coverage and token-efficiency metrics that expose qualitative differences in proof behavior. The results show that current provers remain strongly biased toward easy subtheorems and often solve theorems through long and inefficient tactic traces rather than compact proof plans. TheoremBench therefore provides a more fine-grained view of formal reasoning ability and highlights the importance of structural benchmark design for evaluating Lean4 theorem provers.
QuocViet Pham, Elvir Karimov, Andrey Galichin +1
Skolkovo Institute of Science and Technology · HSE University · Sberbank +1
Large Language Models (LLMs) have made notable progress in automated theorem proving, yet existing formal benchmarks remain limited in both mathematical coverage and difficulty. Most are concentrated in areas that are easier to formalize, such as algebra and elementary number theory, and provide limited coverage of subfields that require deeper reasoning, including mathematical analysis. To address this gap, we introduce MA-ProofBench, to the best of our knowledge, the first formal theorem-proving benchmark dedicated to Mathematical Analysis. The benchmark contains 200 formalized theorems covering 6 core topics and 27 subcategories, including measure and integration theory, complex analysis, and functional analysis. The problems are divided into two difficulty levels, an undergraduate level (Level I, 100 problems) and a Ph.D. qualifying level (Level II, 100 problems), to evaluate how well LLMs perform formal reasoning at different mathematical depths. Each problem is constructed through a human-led, LLM-assisted formalization pipeline followed by independent expert review, ensuring that the formal statements remain faithful to the original mathematics. We evaluate a range of recent general-purpose reasoning models and formal theorem provers on MA-ProofBench. However, most models perform poorly: even the best-performing model, GPT-5.5, achieves only 16% Pass@8 on Level I and 5% on Level II, while most models stay close to 0% on Level II. Further analysis identifies Mathlib hallucinations and incomplete proofs as the two dominant failure modes, while an evaluation on the natural-language version of the benchmark exposes a clear gap between informal and formal reasoning. MA-ProofBench is intended to serve as a reliable reference for tracking progress in formal mathematical reasoning in advanced domains.
We present a new approach for benchmarking Large Language Model (LLM) capabilities on research-level mathematics. Existing benchmarks largely rely on static, hand-curated sets of contest or textbook-style problems as proxies for mathematical research. Instead, we establish an updatable benchmark evaluating models directly on the latest research results in mathematics. This consists of an automatic pipeline that extracts lemmas from arXiv and rewrites them into self-contained statements by making all assumptions and required definitions explicit. It results in a benchmark that can be updated regularly with new problems taken directly from human mathematical research, while previous instances can be used for training without compromising future evaluations. We benchmark current state-of-the-art LLMs, which obtain around 10-15% accuracy in theorem proving (pass@1) depending on the model, showing that there is currently a large margin of progression for LLMs to reach human-level proving capabilities in a research context.
Antoine Peyronnet, Fabian Gloeckle, Amaury Hayat
1Ecole Normale Superieure de Rennes · 2Ecole des Ponts Paris · 3Korean Institute for Advanced Study