ErdosBench leaderboard

Research-math reasoning, judged beyond raw solved counts.

ErdosBench evaluates how models behave on research-level, Erdős-inspired mathematical problems: finding decisive obstructions, using known theorems correctly, producing scoped partial progress, and avoiding unsafe solved claims.

The leaderboard below is based on the full 226-problem run with external judge grades and model-specific proof audits. It is not a formal theorem-certification board; it is a correctness-first signal of which systems generate useful, review-worthy mathematical progress.

226Erdős-inspired candidate problems, with provenance and audit metadata
3,842model/problem judge rows across 17 scored benchmark runs
25four-model A-consensus problems used as high-confidence review anchors
46Tencent HY4-preview self-labelled strong claims proof-audited

External-judge leaderboard

Grades use a compact A/B/C/D/F/M scale: A means mathematically sound and appropriately scoped; B means useful but incomplete or underpowered; C means plausible with a material gap; D/F mark misleading or contradicted claims; M marks a missing row.

Methodology: All runs use APIs in a non-agentic setup with a 100,000-token limit per problem, except GPT models, which run through Codex, and Claude Opus 4.8, which runs through Claude Code.

A sound / scoped B useful C material gap D likely wrong F contradicted M missing
Rank Model Coverage Judge grades Strong claims Proof verification read Avg Leaderboard judgment
1
Fable 5.1 xhighNumerical leader · near tie
226/226rows judged A/B/C/D/F/M: 104 / 112 / 10 / 0 / 0 / 0 64self strong claims Strong audit: A=50 · B=10 · C=4 · D=0 · F=0; partial/triage: A=54 · B=102 · C=6 3.25judge avg, 0–4 Numerical leader by 0.013 points over Opus 5.5 and 0.024 over GPT-6 Astra: an audit-level three-way near tie. Fable combines exceptionally deep, conservatively labelled partial work with only 10 C rows and no D/F/M rows; Astra remains the stronger theorem closer and strong-claim classifier.
2
Claude Opus 5.5 xhighBalanced research yield · near tie
226/226rows judged A/B/C/D/F/M: 104 / 109 / 13 / 0 / 0 / 0 77self strong claims Strong audit: A=57 · B=16 · C=4 · D/F=0; partial/triage: A=47 · B=93 · C=9 3.24judge avg, 0–4 Top-tier full run and an audit-level near tie with Fable and Astra. Opus combines high theorem/counterexample yield, a clean C-grade tail, and excellent confidence calibration. Its main weakness is lower solved-label precision than Astra and several interpretation-dependent strong claims.
3
GPT-6 Astra xhighBest theorem closer · near tie
226/226rows judged A/B/C/D/F/M: 106 / 102 / 18 / 0 / 0 / 0 71self strong claims Strong audit: A=63 · B=7 · C=1 · D=0 · F=0; partial/no-progress: A=43 · B=95 · C=17 3.23judge avg, 0–4 Third numerically in the near-tied leading cluster and the strongest theorem closer in this audit, with 106 A-grade results and no D/F/M rows. Fable leads by 0.024 points through its cleaner C-grade tail, while Astra has stronger explicit strong-claim reliability.
4
GPT-5.6 Sol xhighCleanest low-quality tail
226/226rows judged A/B/C/D/F/M: 78 / 142 / 6 / 0 / 0 / 0 78self strong claims 48 verified · 9 literal · 21 conditional · 0 partial-mislabeled · 0 rejected 3.12judge avg, 0–4 Fourth overall, with the cleanest low-quality tail: only 6 C-grade rows, full coverage, and no D/F/M rows or rejected strong claims. Fable, Opus 5.5, and GPT-6 Astra place ahead through higher A-grade yield.
5
MiMo v2.6 ProReliable strong claims · calibrated confidence
226/226rows judged A/B/C/D/F/M: 79 / 117 / 30 / 0 / 0 / 0 43self strong claims Strong audit: A=36 · B=6 · C=1 · D/F=0; partials: A=43 · B=111 · C=29 3.02judge avg, 0–4 Fifth overall, after GPT-5.6 Sol xhigh and before GLM-5.3 Flash. A high-precision, well-calibrated full run with reliable solved/counterexample labels and strong original scoped results. Fewer decisive closures and a larger material-gap tail keep it below the Fable/Opus/Astra cluster.
6
GLM-5.3 FlashTop GLM-family full run
226/226rows judged A/B/C/D/F/M: 58 / 151 / 15 / 2 / 0 / 0 47self strong claims Strong audit: A=37 · B=6 · C=2 · D=2 · F=0; partials and one fallback fill the remaining rows 2.95judge avg, 0–4 Top GLM-family full run. Very high A/B density, full coverage, and no F-grade claims. Two D-grade strong claims and several proof-gap rows keep it below Fable, Opus 5.5, the two leading GPT runs, and MiMo v2.6 Pro.
7
Tencent HY4-previewBroad partial progress · strong constructive work
226/226rows judged A/B/C/D/F/M: 65 / 133 / 25 / 2 / 1 / 0 46self strong claims Strong audit: A=34 · B=7 · C=3 · D=1 · F=1; partial/triage: A=31 · B=126 · C=22 · D=1 2.93judge avg, 0–4 Strong upper-mid full run with broad useful partial progress, excellent constructions, and complete coverage. It trails MiMo and the top cluster because of weaker theorem-scope control, 25 materially gappy rows, and three D/F outcomes. Elementary obstructions, modular counterexamples, and exact colorings are particular strengths.
8
Muse Spark 1.3Best Meta full run
226/226rows judged A/B/C/D/F/M: 57 / 130 / 39 / 0 / 0 / 0 63self strong claims Strong audit: A=51 · B=11 · C=1 · D=0 · F=0; partials: A=6 · B=119 · C=38 2.86judge avg, 0–4 Best Meta-family full run so far. Full coverage, high A-grade yield, no D/F/M rows, and clean strong-claim discipline. It ranks eighth overall, below Tencent HY4-preview but above Kimi K3 and Muse Spark 1.2.
9
Kimi K3 maxStrongest Kimi-family full run
226/226rows judged A/B/C/D/F/M: 40 / 143 / 43 / 0 / 0 / 0 45self strong claims Strong audit: A=40 · B=2 · C=3 · D=0 · F=0; 3 proof-gap/conditional, 2 partial-mislabeled or triage, 0 rejected 2.74judge avg, 0–4 Strongest Kimi-family full run so far. Full coverage, high A-grade yield, no D/F judge rows, and no rejected strong claims. It ranks ninth overall, ahead of Muse Spark 1.2 and GPT-5.5 xhigh.
10
Muse Spark 1.2Meta frontier model
226/226rows judged A/B/C/D/F/M: 48 / 126 / 47 / 4 / 0 / 1 40self strong claims Strong audit: A=30 · B=6 · C=4 · D=0 · F=0; partials: A=18 · B=120 · C=43 · D=4 · F=0 · M=1; raw fallback=1 2.73judge avg, 0–4 High-yield full run with a clean strong-claim profile and almost no missing output. Muse Spark 1.3 now leads the Meta family, while this run remains just behind Kimi K3 and ahead of GPT-5.5 xhigh.
11
GPT-5.5 xhigh / CodexPrevious correctness-adjusted leader
226/226rows judged A/B/C/D/F/M: 27 / 159 / 40 / 0 / 0 / 0 63self strong claims 30 verified · 9 literal · 16 conditional · 8 partial-mislabeled · 0 rejected 2.68judge avg, 0–4 Reliable full-coverage run with no D/F judge rows, but Fable, Opus 5.5, GPT-6 Astra, GPT-5.6, MiMo v2.6 Pro, GLM-5.3, Tencent HY4-preview, Muse Spark 1.3, Kimi K3, and Muse Spark 1.2 place ahead through stronger averages.
12
Kimi K2.7 CodeEarlier Kimi-family run
220/226rows judged A/B/C/D/F/M: 32 / 151 / 32 / 3 / 2 / 6 50self strong claims Strong audit: A=30 · B=8 · C=7 · D=3 · F=2; solved-label audit has 7 proof gaps and 4 rejected 2.62judge avg, 0–4 Best at compact constructions and counterexamples, but missing rows and proof-gap/rejected solved labels reduce trust.
13
Claude Opus 4.8 maxBest reviewer and partial-depth model
226/226rows judged A/B/C/D/F/M: 22 / 135 / 69 / 0 / 0 / 0 37self strong claims 9 green natural · 4 green literal · 6 amber partial/overclaimed · 2 red 2.51judge avg, 0–4 Safest broadly: strong proof hygiene and scoped partials, but fewer decisive breakthroughs than the top-ranked models.
14
GLM-5.2Strong but uneven full-run entrant
222/226rows judged A/B/C/D/F/M: 35 / 95 / 82 / 7 / 3 / 4 33self strong claims Strong audit: A=23 · B=3 · C=3 · D=3 · F=1; partials: 12 A · 92 B · 79 C · 4 D · 2 F 2.402.36 adjusted Strong partial mass and clean core results, but a large gappy middle band and several invalid theorem-scope jumps keep it below Opus 4.8.
15
Mistral Large 4Exploratory research · inconsistent final verdicts
222/226rows judged · 4 missing A/B/C/D/F/M: 22 / 121 / 72 / 2 / 5 / 4 31self strong claims Strong audit: A=13 · B=10 · C=4 · D=1 · F=3; partial/triage: A=9 · B=111 · C=68 · D=1 · F=2; M=4 2.38judge avg, 0–4 Some excellent exact arguments, constructive counterexamples, and statement debugging, but four missing rows, 72 C-grade rows, seven D/F rows, and contradicted strong claims limit reliability. More useful for candidate approaches than autonomous theorem closure.
16
Qwen 3.7 MaxUseful full-coverage corroborator
226/226rows judged A/B/C/D/F/M: 18 / 113 / 91 / 3 / 1 / 0 20self strong claims 12 solved labels: 5 complete · 3 literal/conditional · 2 partial/overclaimed · 2 incorrect/not solved 2.37judge avg, 0–4 Good when it agrees with others, but isolated solved claims are high-risk and proof hygiene is weaker.
17
MiniMax M3Full coverage, weaker proof hygiene
226/226rows judged A/B/C/D/F/M: 15 / 77 / 113 / 12 / 9 / 0 27self strong claims Strong claims: A=9 · B=1 · C=6 · D=5 · F=6; partials: 6 A · 75 B · 107 C · 7 D · 3 F 2.11judge avg, 0–4 Complete coverage and some useful compact results, but C-heavy partials and unreliable solved labels place it below Qwen.

The safest public signal is not raw solved count. ErdosBench separates clean theorem-style proofs, literal or convention-dependent resolutions, conditional arguments, useful partials, and rejected claims.

Why ErdosBench is valuable

Decisive obstruction finding

Does the model spot a hidden divisor bound, coloring invariant, degeneracy, or counterexample that changes the problem?

Known theorem use

Does it deploy the right theorem family without hallucinating scope, constants, or missing hypotheses?

Proof hygiene

Does it distinguish solved, conditional, partial, literal, and rejected claims instead of overmarketing a sketch?

Review yield

Does it produce enough high-quality, review-ready mathematical material to justify expert attention?

Leaderboard read: Fable 5.1 xhigh leads at 3.254, followed by Claude Opus 5.5 xhigh at 3.241 and GPT-6 Astra xhigh at 3.230. These runs form a three-way top-tier cluster, with only two or three row-grade decisions separating adjacent places.

Fable has the cleanest partial-progress profile among the leading three; Astra remains the most precise theorem closer. Opus balances high theorem yield, a cleaner weak tail than Astra, and excellent confidence calibration, while trailing Astra on strong-verdict precision.

GPT-5.6 Sol xhigh ranks fourth and retains the cleanest weak tail, with only 6 C-grade rows.

MiMo v2.6 Pro ranks fifth at 3.022, between GPT-5.6 Sol xhigh and GLM-5.3 Flash. Its strong-claim A-rate is 83.7%, with excellent confidence calibration and compact constructive counterexamples; its larger partial-progress band and 30 C rows limit theorem-closing yield. GLM-5.3 Flash is the top GLM-family run at #6.

Tencent HY4-preview scores 2.934, between GLM-5.3 Flash and Muse Spark 1.3. It produces useful A/B mathematics on 198/226 rows (87.6%), with strong elementary obstructions and constructive counterexamples. Its 73.9% strong-claim A-rate, 25 C rows, and three D/F outcomes call for stricter theorem-scope and verdict checks.

Muse Spark 1.3 ranks eighth and remains the strongest Meta-family run. Kimi K3 remains the strongest Kimi-family run at #9.

Muse Spark 1.2 and GPT-5.5 xhigh form the next full-run tier, ahead of Kimi K2.7.

Claude Opus 4.8 remains the best reviewer/partial-depth model.

GLM-5.2 is a strong but uneven entrant after full partial judging. Mistral Large 4 scores 2.383, just above Qwen and below GLM-5.2’s displayed 2.40 (2.36 adjusted). These runs occupy the same broad tier; Mistral offers useful constructions but needs strict final-answer and proof checks.

Qwen is best used for corroboration, and MiniMax M3 is a full-coverage lower baseline with weaker solved-label proof hygiene.

Proof audits: why raw solved counts are not enough

Model Scope audited Verification buckets Takeaway
Fable 5.1 xhigh
64 self strong claims; 162 partial or triage rows 50 A strong 10 B strong 4 C strong 0 D/F strong 54 A partial/triage 102 B partial/triage 6 C partial/triage Numerical leader with 104 A-grade rows, only 10 C-grade rows, and no D/F/M rows. Its defining strength is the 54 A-grade results conservatively labelled partial or triage; 14 explicit strong claims remain below A.
Claude Opus 5.5 xhigh
77 self strong claims; 149 partial, triage, or no-progress rows 57 A strong 16 B strong 4 C strong 0 D/F strong 47 A partial/triage 93 B partial/triage 9 C partial/triage Second numerically in the leading cluster: 104 A-grade rows, only 13 C rows, and no D/F/M rows. Strong-claim A-rate is 74.0%; 140/149 non-strong rows are A/B. Interpretation-dependent or technically unaudited strong claims remain its main weakness.
GPT-6 Astra xhigh
71 self strong claims; 155 partial or no-progress rows 63 A strong 7 B strong 1 C strong 0 D/F strong 43 A partial 95 B partial 17 C partial Highest theorem-level yield: 106 A-grade rows, including 43 self-labelled partials. No D/F/M rows or rejected strong claims; eight technically ambitious strong claims remain below A pending stronger verification.
GPT-5.6 Sol xhigh
78 self strong claims 48 verified 9 literal 21 conditional 0 partial-mislabeled 0 rejected Fourth-highest full-run score and the cleanest weak tail: 78 A-grade rows, only 6 C-grade rows, and no rejected strong claims.
MiMo v2.6 Pro
43 self strong claims (17 solved, 26 counterexamples); 183 partial-progress rows 36 A strong 6 B strong 1 C strong 0 D/F strong 43 A partial 111 B partial 29 C partial Strong-claim A-rate of 83.7%, with no D/F/M rows and confidence that falls meaningfully with grade. Six B-grade strong claims depend on interpretation or incomplete scope; Problem 118 is the sole C-grade strong claim. Partial quality is the main weakness: 154/183 partials are A/B (84.2%), with 29 materially gappy rows.
GLM-5.3 Flash
47 self strong claims; 179 partial or fallback rows 37 A strong 6 B strong 2 C strong 2 D strong 0 F strong High review yield with 209 A/B rows and no F-grade claims. Two overpromoted strong claims - Problems 28 and 31 - keep its proof hygiene below the leader.
Tencent HY4-preview
46 self strong claims (30 solved, 15 counterexamples, 1 likely false); 180 partial, triage, or no-progress rows 34 A strong 7 B strong 3 C strong 1 D strong 1 F strong 31 A partial/triage 126 B partial/triage 22 C partial/triage 1 D partial/triage Strong-claim A-rate of 73.9%, with 157/180 non-strong rows graded A/B (87.2%). Problem 28 overstates a theorem’s scope; Problem 51 is a contradicted strong claim with a defective moment argument; Problem 218 imports an unsupported squarefree-gap asymptotic. All 226 rows are present, but confidence alone does not identify its worst mistakes.
Muse Spark 1.3
63 self strong claims; 163 partial-progress rows 51 A strong 11 B strong 1 C strong 0 D/F strong 6 A partial 119 B partial 38 C partial Strongest Meta-family audit: no D/F/M judge rows and no rejected strong claims. Its main remaining risk is a 39-row material-gap band.
Kimi K3 max
45 self strong claims 40 A accepted 2 B triage/partial-mislabeled 3 C proof-gap/conditional 0 rejected Strongest Kimi-family audit so far: no D/F judge rows and no rejected strong claims, with five claims correctly held below A pending stronger proof or scope.
Muse Spark 1.2
40 self strong claims; 186 partial-progress rows 30 A strong 6 B strong 4 C strong 0 D/F strong 18 A partial 120 B partial 43 C partial 4 D partial 1 missing/raw fallback Clean strong-claim audit with no rejected solved or counterexample claims. The main risk sits in the middle band: 47 C-grade rows and 4 D-grade partials still require proof closure or scope correction.
GPT-5.5 xhigh / Codex
63 non-partial attempted resolutions30 verified 9 literal 16 conditional 8 partial-mislabeled 0 rejected Former full-run leader; conditional and partial-mislabeled rows still require expert extraction before public solved claims.
Kimi K2.7 Code
30 solved-label claims; 50 strong claims deep-audited6 verified 4 literal 4 conditional 5 partial-mislabeled 7 proof gaps 4 rejected Earlier Kimi-family run; solved labels are high-value but need strict proof-checking.
Claude Opus 4.8 max
21 solved-label claims9 green natural 4 green literal 6 amber 2 red Best reviewer profile: careful partials and caveats, but not self-certifying on solved labels.
GLM-5.2
33 strong claims; 189 partial-progress rows23 A strong 3 B strong 3 C strong 4 D/F strong 12 A partial 92 B partial 79 C partial 6 D/F partial Strong full-run entrant: many useful partials, but theorem-scope mistakes and invalid partials keep proof hygiene below Opus 4.8.
Mistral Large 4
31 self strong claims (24 solved, 7 counterexamples); 191 partial, triage, or no-progress rows; 4 missing 13 A strong 10 B strong 4 C strong 1 D strong 3 F strong 9 A partial/triage 111 B partial/triage 68 C partial/triage 3 D/F partial/triage 4 missing Only 13/31 strong claims are A (41.9%); four strong claims are D/F. Useful exploratory work often survives, but headlines and verdicts can contradict the final reasoning. The run has 72 C rows and seven D/F rows overall; absent Problems 2, 94, 180, and 215 receive M and zero score in the 226-row average.
Qwen 3.7 Max
12 solved-label claims5 complete 3 literal/conditional 2 partial 2 incorrect/not solved Useful corroborator; isolated solved claims should be treated as high-risk.
MiniMax M3
27 strong claims; 198 partial-progress rows9 A strong 1 B strong 6 C strong 11 D/F strong 6 A partial 75 B partial 107 C partial 10 D/F partial Full coverage, but solved labels are unreliable and the partial profile is C-heavy; best used as lower baseline and failure-mode data.

Model-level diagnosis and post-training opportunities

Model Diagnosis
Fable 5.1 xhigh

Strengths: the numerical leader, with 104 A-grade and 112 B-grade results, only 10 C-grade rows, no D/F/M rows, and 54 A-grade results that it conservatively labelled partial or triage. Its confidence is meaningfully calibrated, and the closed-book run produces unusually deep, self-contained research progress. Weaknesses: 14 of 64 explicit strong claims are downgraded to B or C, several conclusions depend on reconstructed meanings for underdefined statements, and the lack of tools limits literature and certificate-level reproducibility. Post-training: preserve its calibrated, conservative partial labels while improving strong-verdict precision and adding tool-backed checks for citations, definitions, computation, and specialist arguments.

Claude Opus 5.5 xhigh

Strengths: balanced top-tier research yield, with 104 A-grade rows, only 13 C rows, distinctive constructions on Problems 79 and 166, deep partial progress, and useful confidence calibration (mean 0.786) in a closed-book, tool-free run. Weaknesses: 20 of 77 strong claims are downgraded to B or C; solved-label precision trails Astra, several claims resolve reconstructed definitions, and technically ambitious proofs need specialist reproduction. It also misses decisive ideas on Problems 20, 85, and 91. Post-training: preserve its calibrated confidence and original construction ability while requiring exact statement alignment, explicit remaining-gap checks, and reproducible theorem or certificate verification before strong verdicts.

GPT-6 Astra xhigh

Strengths: third numerically in the near-tied leading cluster and the strongest theorem closer, with the highest A-grade yield at 106, exceptional theorem and counterexample output, broad mathematical technique, and 43 self-labelled partials that already contain sound A-grade progress. Weaknesses: its confidence scores are compressed near one and do not identify which rows need review; 18 C-grade rows form a wider weak tail than Fable, Opus 5.5, or GPT-5.6, while seven B-grade and one C-grade strong claims require specialist reproduction or an unconditional argument. Post-training: calibrate confidence against proof status, retain its conservative verdict labeling, and add specialist verification signals for long sieve, Fourier, set-theoretic, and representation-theoretic arguments.

GPT-5.6 Sol xhigh

Strengths: the fourth-highest full-run score and the cleanest low-quality tail, with decisive obstruction finding, broad theorem deployment, 78 A-grade rows, only 6 C-grade rows, and no rejected strong claims. Weaknesses: 142 rows remain useful partials, often stopping at one-sided bounds, corrected formulations, reductions, or finite variants; literal and conditional wins are valid but not all equally deep discoveries. Post-training: target the remaining exact asymptotics, uniform analytic number theory, and extremal-stability gaps with stronger theorem-dependency and proof-completion signals.

MiMo v2.6 Pro

Strengths: reliable solved and counterexample labels, with 36 of 43 strong claims accepted as A, 79 A-grade rows overall, no D/F/M rows, compact constructive obstructions, and self-contained proofs. Confidence is well calibrated: approximately 0.77 on A rows, 0.58 on B rows, and 0.42 on C rows. Weaknesses: partial depth and theorem closure trail the leading cluster; 29 of 183 partials receive C, and several decisive arguments are missed. Six B-grade strong claims and the C-grade claim on Problem 118 depend on reconstructed definitions or incomplete scope; Problem 182 imports an extremal lower bound unavailable in the claimed generality. Post-training: preserve its cautious verdicts and calibrated confidence while strengthening exact statement alignment, theorem-hypothesis checks, and proof completion, especially for uniform analytic-number-theory estimates and local-to-global arguments.

GLM-5.3 Flash

Strengths: the top GLM-family full run, with full coverage, 58 A-grade rows, 151 useful B-grade rows, and especially strong divisor, coloring, CRT/coset, and geometric obstruction finding. Weaknesses: Problems 28 and 31 show its main failure mode: an elegant cycle or sumset argument is promoted before the theorem scope or key step is secure; two additional strong claims remain C-grade. Post-training: train a final adversarial proof pass that checks implication direction, theorem hypotheses, and the weakest globalizing step before a solved label is emitted.

Tencent HY4-preview

Strengths: broad research yield, with 65 A-grade and 133 B-grade rows, full coverage, short arithmetic obstructions, modular constructions, exact colorings, and strong statement debugging. Set systems and algebraic combinatorics are especially productive, and confidence generally separates A/B/C work meaningfully. Weaknesses: 12 of 46 strong claims remain below A, including one D and one F; 25 rows have material gaps and three are D/F overall. Theorem-scope errors on Problems 28 and 218 and heuristic or moment overclaims on Problems 51, 80, and 93 undermine otherwise polished arguments. High confidence on the worst strong claims and limited certificate packaging increase review risk. Post-training: preserve its constructive instincts while requiring exact theorem hypotheses, explicit uniformity and integrability checks, and a final distinction between proved results, heuristics, and reconstructed definitions. Add reproducible checks before promoting technically original work to strong verdicts.

Muse Spark 1.3

Strengths: the best Meta-family full run, with 57 A-grade rows, 130 useful B-grade rows, no D/F/M rows, and 51 of 63 strong claims accepted as A. It is especially effective at decisive obstructions, scoped reductions, and compact counterexamples. Weaknesses: 39 C-grade rows remain materially gappy, and 12 strong labels are downgraded to B or C because a theorem-scope leap, unresolved uniformity input, or local construction prevents full closure. Post-training: emphasize proof-completion checks, global-vs-local scope, and calibrated stopping when a strong research direction is not yet a theorem.

Kimi K3 max

Strengths: the strongest Kimi-family full run, with decisive obstruction finding, compact counterexamples, strong theorem selection, 40 A-grade rows, and 143 useful B-grade rows. Weaknesses: 43 rows retain material gaps, and Problems 9, 38, and 125 show the main failure mode: a sketched lemma, long case analysis, or conditional construction is promoted to a solved or counterexample label too early. Post-training: reinforce theorem-dependency checks, unconditional-vs-conditional labeling, and a final proof-debt review before allowing strong verdicts.

Muse Spark 1.2

Strengths: a high-yield full-bench entrant with decisive obstruction finding, strong theorem selection, 48 A-grade rows, 126 useful B-grade rows, and 30 accepted strong claims with no D/F strong-claim failures. Weaknesses: the 47 C-grade and 4 D-grade rows cluster around unproved analytic-number-theory uniformity, long case analyses, conditional theorem transfers, and mis-scoped interpretations; one row required a raw-preserving fallback. Post-training: emphasize proof closure, hypothesis and uniformity checks, verdict calibration, and machine-checkable certificate evidence before promoting promising research directions to strong claims.

GPT-5.5 xhigh / Codex

Strengths: previous full-run leader, excellent at decisive obstructions, exact formulas, and literal counterexamples. Weaknesses: many isolated strong claims are conditional, wording-dependent, or partial-mislabeled. Post-training: our audited rows can train stronger verdict calibration: require theorem dependencies, literal-vs-natural statement tags, and a final “what remains unproved?” check before a solved label is allowed.

Kimi K2.7 Code

Strengths: creative earlier Kimi-family run, strong on compact constructions and counterexamples. Weaknesses: solved labels sometimes hide proof gaps, false uniformity assumptions, or theorem-scope drift. Post-training: our accepted-vs-rejected Kimi pairs are ideal for DPO and process-reward training focused on quantifier discipline, uniformity checks, and “creative idea but not yet proof” downgrades.

Claude Opus 4.8 max

Strengths: best reviewer profile, strong gap accounting, and many well-scoped partials. Weaknesses: underclaims short decisive obstructions and sometimes keeps a solved subproblem in “partial” mode. Post-training: our data can teach partial-to-theorem extraction: when a divisor bound, coloring invariant, or literal obstruction already closes the statement, promote it confidently while preserving caveats.

GLM-5.2

Strengths: strong entrant with many real A/B partials and good theorem-aware reductions. Weaknesses: theorem importation is uneven; some partials cite stronger-than-available results or make local-to-global jumps. Post-training: our full partial audit can train theorem-scope verification: state the exact theorem used, check hypotheses, and classify each row as strong partial, useful partial, heuristic, or invalid.

Mistral Large 4

Strengths: persistent exploratory reasoning, explicit constructions, statement debugging, informative confidence separation, and 121 useful B-grade rows alongside 22 A-grade results. Its best work gives clean finite classifications and decisive obstructions. Weaknesses: only 13 of 31 strong claims receive A; three are contradicted and one likely wrong. Failed approaches often remain beside the surviving argument, leaving the summary, verdict, and proof inconsistent. A 72-row C band, seven D/F rows, four missing problems, weak reproducibility packaging, and long responses increase review cost. Post-training: require a final consistency pass that removes failed attempts, restates the surviving proof, checks exact theorem scope and simple counterexamples, and aligns the headline, verdict, and remaining gaps before a solved label. Preserve its construction ability while improving coverage and proof completion.

Qwen 3.7 Max

Strengths: useful full-coverage corroborator with many reasonable theorem-family suggestions. Weaknesses: fewer decisive accepted results and a tendency to phrase plausible programs as if they were complete proofs. Post-training: our judge labels can train missing-lemma detection: separate proved statement, conjectural extension, and required external lemma before producing a final answer.

MiniMax M3

Strengths: full coverage and a few good compact obstructions, literal counterexamples, and underclaimed A-level partials. Weaknesses: C-heavy partial profile and unreliable solved labels, with many D/F strong claims caused by wrong theorem scope, wrong recurrence, or wrong problem interpretation. Post-training: our data can train solved-label discipline: demote bad proofs, preserve useful subclaims, and reward explicit statement parsing before invoking a theorem.

Benchmark design

What is measured?

Solving is only one signal. ErdosBench also scores statement debugging, counterexample search, theorem selection, proof-gap detection, finite checks, and scoped partial progress.

Why it matters: these are the skills needed for research assistants, theorem-proving agents, and verifier-backed RLVR loops.

What is protected?

The 226 source records are research candidates, not a public list of certified open problems. Private splits, hidden verifier keys, expert rubrics, and review queues stay sealed.

Public reports show aggregate skill, proof hygiene, and leaderboard movement without burning holdout statements.

1Candidate problem corpus with provenance and risk notes
2Full model runs with structured verdicts and evidence
3External judge grades and proof-verification passes
4Review queues for expert mathematicians and verifier authors
5Training data: SFT, critique, reward-model, and RLVR views

Access

Run ErdosBench on your model.

Ulam can run private evaluations, build domain-specific research-math benchmarks, and convert failures into trainable proof-process data. Contact us for hidden-split access, custom model comparisons, or verifier-backed RLVR environments.