EULER: Exploring Underused Links with Evidence-Checked Return for Multi-Agent Mathematical Discovery
Abstract
Mathematical communities work with different objects, invariants, and tools, so transferring a problem across them is expensive and often skipped. We present EULER, a multi-agent system that takes such a transfer--a bridge--as its unit of search. Around a fixed conjecture, EULER runs direct, adjacent-domain, and distant-domain routes in competition; a bridge keeps its budget only if it supplies an operation the source representation cannot execute and its target-side evidence returns to the original statement along a checked implication. Six ordered stress tests reject invalid bridges before expensive search begins. We evaluate EULER on 120 recent conjectures. The conjectures were frozen before search and screened for contamination, and are drawn from public papers by authors who had recently published in the Journal of Combinatorial Theory, Series A, a leading journal in combinatorics. EULER produced 10 proofs and 3 refutations, plus 45 scoped partial results. Two mechanisms held up under ablation: bridge-specific stress tests cut incorrect conclusions from 9 to 3, and bridge material combined with a target-native operation yielded a positive interaction of +4.2 resolved tasks that neither factor produced alone. Domain distance did not reliably predict success; executable operation gain and valid return did.
Figures & tables
| Role | Reads | Must deliver | State authority |
|---|---|---|---|
| Controller | Fixed task definition, route pool, verification records, costs | Next task, budget, and stopping reason | Queues and quotas in the task graph |
| Exploration worker | Source statement, allowed material, failure records | Bridge card, proof sketch, or counterexample candidate | Candidate creation only |
| Target checker | Target statement, artifact, and environment | Target-side validation record | Target-evidence axis |
| Bridge checker | Map, assumption differences, return template | Preservation result, counterexample, or open obligation | Bridge state and dependency edges |
| Independent replayer | Registered artifact, dependencies, tool version | Reproducible output, axiom list, and error class | Machine-evidence axis |
| Source reviewer | Fixed statement, bridge records, target evidence | Coverage table, source verdict, and scope | Root-conclusion candidate |
| Signal | Question | Checkable justification |
|---|---|---|
| operation gain | What can the target domain do that the source route cannot | Interface to a checker, exact algorithm, strong invariant, or established theorem |
| certificate compression | Is the target certificate, including its return path, shorter | Certificate size, number of obligation nodes, and independent checking steps |
| tool absence | Does the source side already provide an equivalent operation | Tool inventories for direct and adjacent-domain routes |
| mapping loss | What structure disappears in translation | Failure of injectivity or surjectivity, parameter merging, and omitted objects |
| return cost | How does the target result support the source statement | Return steps, open branches, and required expertise |
| rejection cost | What is the cheapest decisive test | A smallest case, boundary case, round-trip check, or dimensional check |
| Stress test | Passing condition | Typical failure |
|---|---|---|
| Direction | The target result supports the required source conclusion along the registered implication | Using to treat a proof of as a proof of |
| Assumptions | Every target assumption follows from or is proved separately | Hiding positive definiteness, finiteness, general position, or another condition inside a definition |
| Boundary | The map remains in scope on smallest, degenerate, and extreme objects | Failure at the zero object, low dimension, a parity change, or a dimension jump |
| Round trip | recovers the structure used by the source conclusion | Merging two source objects that the argument must distinguish |
| Tool | supplies an executable operation absent from source routes | Rephrasing the problem without adding a checker or theorem interface |
| Return | Filling the frozen return template covers | Leaving an exceptional branch, a joint choice, or a parent-level composition step unresolved |
| Evidence axis | Central question | Typical states |
|---|---|---|
| Machine | Can an explicit object be replayed by an independent checker | Unchecked, certificate accepted, kernel accepted, replay failed |
| Semantic | Does the formal or target statement faithfully express the source statement | Unchecked, scope in question, human confirmed, mechanically equivalent |
| Independent review | Do independent reviewers accept the proof-critical argument | Unreviewed, revision required, accepted, disagreement |
| Composition | Do the local results jointly imply the parent claim | Local leaf, partial closure, closure complete, withdrawn |
| Obligation | Relation to check | Common failure |
|---|---|---|
| Parameter coverage | The union of the child scopes covers the parent statement | A sparse case is presented as the general case |
| Interface compatibility | Each output satisfies every assumption of the next lemma | Confusing quotient objects, sequences, and sets |
| Invariant compatibility | Group operations, lengths, and sign conventions agree across maps | Switching between left and right actions or counting conventions |
| Well-founded descent | Every recursive step strictly decreases the frozen measure | A cyclic dependency or a zero-step descent |
| Joint choice | Local existential claims can be realized by the same object | Combining separate existence claims into simultaneous existence |
| Boundary coverage | Smallest, degenerate, and extreme parameters close separately | Division, nonemptiness, or invertibility fails at the boundary |
| Outcome | Count | Share | Admission criterion |
|---|---|---|---|
| Proved | 10 | 8.3% | An independently reviewed proof chain covers the fixed statement |
| Refuted | 3 | 2.5% | A concrete object satisfies every premise and violates the conclusion |
| Conditional result | 27 | 22.5% | Additional assumptions are explicit and the conclusion is proved under them |
| Local theorem | 18 | 15.0% | The result covers a proper subclass or a finite parameter range |
| Unresolved | 59 | 49.2% | No valid conclusion on the full source problem is available at the budget limit |
| Incorrect source conclusion | 3 | 2.5% | The target artifact is valid, but its return direction or coverage is wrong |
| Structural stratum | Verified | Conditional | Local | Unresolved | Incorrect | Total |
|---|---|---|---|---|---|---|
| Sparse bridge | 2 | 8 | 5 | 14 | 1 | 30 |
| Executable refutation | 5 | 5 | 3 | 17 | 0 | 30 |
| Structural transfer | 4 | 8 | 6 | 10 | 2 | 30 |
| Language and formalization | 2 | 6 | 4 | 18 | 0 | 30 |
| Total | 13 | 27 | 18 | 59 | 3 | 120 |
| Case | Bridge type | New operation | Decisive stress test | Source-side outcome |
|---|---|---|---|---|
| Zhao | Distant-domain computation | Occurrence encoding and exhaustive enumeration | Encoding fidelity, length bounds, and witness return | Counterexample |
| AJT(5) | Adjacent-domain structure | Support-graph decomposition and transfer counting | Scope of dense rows | All-dimensional local theorem |
| Gao | Multi-bridge composition | Zero-sum tools, descent, and Lean | Parameter coverage, joint choice, and semantic correspondence | Candidate theorem with partial formalization |
| Strategy | Verified resolutions | Incorrect conclusions | Other outcomes | Target-side validations |
|---|---|---|---|---|
| Direct search | 8 | 4 | 108 | – |
| Adjacent-domain bridges | 9 | 3 | 108 | 15 |
| Random distant-domain bridges | 8 | 4 | 108 | 18 |
| Retrieved distant-domain bridges | 8 | 3 | 109 | 20 |
| Joint bridge pool, no bridge-specific tests | 12 | 9 | 99 | 27 |
| Full system | 13 | 3 | 104 | 26 |
| Return rule | Correctly accepted | Incorrectly accepted | Withheld |
|---|---|---|---|
| Target checker only | 16 | 10 | 0 |
| Matched-information generic stress test | 15 | 6 | 5 |
| Bridge-specific stress test | 13 | 3 | 10 |
| Strict certification | 12 | 0 | 14 |
| First decisive outcome | Adjacent-domain bridge | Distant-domain bridge |
|---|---|---|
| Direction mismatch | 16 | 27 |
| Unmet added assumption | 13 | 25 |
| Boundary or round-trip failure | 19 | 24 |
| No gain from a target-native operation | 31 | 13 |
| Return cost too high | 13 | 10 |
| Passed and entered deep search | 18 | 15 |
| Source-native tool interface | Target-native operation | |
|---|---|---|
| No bridge material | 7.2 | 7.8 |
| Bridge material | 8.0 | 12.8 |
| Selector | Mean verified resolutions /120 | Seed standard deviation |
|---|---|---|
| Semantic similarity | 7.4 | 0.9 |
| Early rejection cost | 8.1 | 0.8 |
| Uniform selection | 8.6 | 1.0 |
| Automated representation meta-search | 9.8 | 0.8 |
| Correspondence recommendation | 10.7 | 0.7 |
| Gain-loss ranking | 12.8 | 0.8 |
| Budget rule | Verified resolutions | Incorrect returns | Rejected-bridge budget | Normalized cost ratio |
|---|---|---|---|---|
| Even adjacent/distant split | 10 | 5 | 32% | 1.39 |
| Fixed adjacent preference | 10 | 4 | 28% | 1.34 |
| One-shot first-round allocation | 11 | 4 | 24% | 1.26 |
| Round-by-round stress-test feedback | 13 | 3 | 17% | 1.12 |
| Model condition | Mean verified resolutions | Mean incorrect returns | Compute cost/task |
|---|---|---|---|
| Model A | 10.2 | 4.2 | 486 |
| Model B | 9.8 | 3.8 | 482 |
| Model C | 8.9 | 4.6 | 477 |
| Homogeneous multi-agent | 11.1 | 3.7 | 484 |
| Heterogeneous composition | 12.8 | 3.0 | 485 |
| Strategy | Compute cost | Million tokens | Wall-clock hours | Bridge min | Math review min | State min | Combined cost/task | Normalized cost/resolution |
|---|---|---|---|---|---|---|---|---|
| Direct search | 170 | 2.6 | 3.1 | 0 | 31 | 12 | 313 | 4695 |
| Adjacent-domain bridges | 187 | 2.9 | 3.6 | 18 | 36 | 14 | 414 | 5520 |
| Random distant-domain bridges | 214 | 3.3 | 4.2 | 31 | 43 | 15 | 511 | 7665 |
| Retrieved distant-domain bridges | 225 | 3.4 | 4.4 | 29 | 45 | 16 | 525 | 7875 |
| Full system | 238 | 3.6 | 4.8 | 36 | 44 | 19 | 568 | 5243 |
Appendix figures & tables13 assets
Supplementary material from the paper’s appendix.
Appendix
| Field | Content |
|---|---|
| Exact statement | Object domain, quantifiers, parameters, conclusion, and statement version |
| Exact negation | Premises a counterexample must satisfy and the conclusion it must violate |
| Admissible evidence | Natural-language proof, concrete witness, formal proof, program certificate, or a combination |
| Boundary set | Minimal, degenerate, extreme, and first nontrivial cases |
| Source-side decision | Operational definitions of the six mutually exclusive outcomes |
| Contamination cutoff | Conjecture date, retrieval cutoff, and admissible document versions |
| Field | Content |
|---|---|
| Identity | Task version, route identifier, bridge family, bridge version, proposer, and time |
| Source and target | Object types, statements, parameters, encodings, and mathematical communities |
| Maps | , candidate back-map , direction, domain, and exceptional set |
| Preservation relation | Invariants, order, invertibility, counts, or semantic correspondence |
| Target mechanism | New operation supplied by a theorem, algorithm, verification procedure, or representation |
| Source-return contract | Required certificate, covered region, and composition interface on the source side |
| Candidate source | Main retrieval signal | Required object | Check before stress testing |
|---|---|---|---|
| Direct route | Source terminology, theorem neighborhood, and standard reductions | Source-side proof or counterexample plan | Same scope as the fixed statement |
| Adjacent-domain bridge | Shared objects, classical associated quantities, and standard functors | Explicit map and an adjacent-domain mechanism | At least one preserved quantity |
| Distant-domain random | Eligible random sample from the target-mechanism catalog | Explicit object transformation | Interpretable direction and executable target operation |
| Distant-domain retrieval | Structural fingerprint, certificate type, and new operation | Map, target mechanism, and source-return sketch | Operation not duplicated in the direct pool |
| Expert proposal | Expertise spanning two domains and known failure patterns | Reviewable bridge record | Complete source, scope, and reviewer fields |
| Formalization route | Statement structure, library lemmas, and decidable fragments | Semantic map and Lean goal | Registered environment, quantifiers, and permitted axioms |
| Code | Recorded fact | Valid reopening condition |
|---|---|---|
| DIR | The target conclusion has the wrong direction for the required source conclusion | Replace the target theorem or use a valid converse |
| ASM | The target mechanism requires an assumption absent from the source problem | Prove the assumption, state a conditional result, or replace the bridge |
| BND | A minimal, degenerate, or extreme object violates the map | Restrict the scope and handle the failed region separately |
| RT | The round trip loses proof-critical structure or merges distinct source objects | Change the encoding, add identifiers, or revise the source return |
| ACT | A matched-budget probe produces no new operation | Use a different target mechanism |
| RET | The target evidence does not cover the fixed source statement | Add a coverage lemma or change the source-side outcome |
| Directory | Main files | Reproducible check |
|---|---|---|
| contracts/ | Fixed statement, exact negation, boundaries, and evidence contract | Check the denominator and statement version |
| routes/ | Bridge records, route lineage, retrieval sources, and failure ledger | Reconstruct the candidate pool and route identities |
| stress_tests/ | Six stress-test records, object witnesses, and costs | Recompute the survival funnel and stopping decisions |
| artifacts/ | Proofs, counterexamples, programs, Lean files, and output summaries | Check the mathematical objects independently |
| verification/ | Target, bridge, replay, semantic, and source-side verification records | Check evidence scope and composition |
| outcomes/ | Six outcome categories, blinded decisions, and release tiers | Reconstruct primary and error endpoints |
| Dimension | Score 0 | Score 1 | Score 2 |
|---|---|---|---|
| Object type | Same object and encoding | Standard derived object or specialization | Changed object type and combinatorial structure |
| Theory | Same theory | Standard adjacent branch | Different basic definitions and theorem system |
| Governing invariant | Original invariant retained | Classical associated quantity | New governing invariant |
| Correspondence length | One standard equivalence | Two or three established steps | New composition of maps required |
| Expert community | Complete review within one domain | Joint review by adjacent domains | Primary review by another community |
| Component | Score 0 | Score 2 | Score 4 |
|---|---|---|---|
| No new operation | New verification procedure or local algorithm | Decisive algorithm, strong invariant, or proof interface | |
| No reduction in evidence length | Some obligations are compressed | Target certificate plus return is substantially shorter | |
| An equivalent tool exists in the source routes | The source tools can simulate it only indirectly | Neither the direct nor adjacent-domain pool has a comparable operation | |
| All proof-critical structure is preserved | Exceptions or merged objects can be enumerated | The map loses structure required by the source conclusion | |
| One standard source-return step | Several local obligations are needed | Source return nearly repeats the original proof | |
| A small example decides the route | A local program or expert check is required | Cost approaches that of a complete target proof |
| Type | Fixed input | Preferred test | Output object |
|---|---|---|---|
| Direction | and required result type | Implication direction and contrapositive | Valid result direction or reverse task |
| Assumption | , target premises, and | Premise difference and missing-assumption witness | New subproblem or conflicting object |
| Boundary | Minimal, degenerate, and extreme objects | Low-order enumeration and symbolic boundaries | Boundary certificate or counterexample |
| Round trip | and preserved quantities | Compare and invariants | Preservation proof or information loss |
| Operation | and source-tool inventory | Matched-budget paired probe | New operation and incremental artifact |
| Source return | Fixed source-return template | Obligation filling and coverage check | Source-side chain or open branch |
| Condition | Direct | Adjacent pool | Distant pool | Retrieval | Target operation | Specific tests | Source-return rule |
|---|---|---|---|---|---|---|---|
| Direct search | 1 | 0 | 0 | 0 | 0 | 0 | Direct source-side review |
| Adjacent-domain bridges | 1 | 1 | 0 | 0 | 1 | 0 | General source return |
| Distant-domain random | 1 | 0 | 1 | 0 | 1 | 0 | General source return |
| Distant-domain retrieval | 1 | 0 | 1 | 1 | 1 | 0 | General source return |
| Combined, no specific tests | 1 | 1 | 1 | 1 | 1 | 0 | General source return |
| Full system | 1 | 1 | 1 | 1 | 1 | 1 | Bridge-specific source return |
| Distant retrieval resolved | Distant retrieval unresolved | Total | |
|---|---|---|---|
| Full system resolved | 7 | 6 | 13 |
| Full system unresolved | 1 | 106 | 107 |
| Total | 8 | 112 | 120 |
| Audit stage | Count | Decision and recorded evidence |
|---|---|---|
| Overlap alert | 146 | Retain the matched text, date, version, query, and alert type for curator review |
| Substantive answer cue | 23 | Record the proof idea, counterexample clue, answer-bearing theorem, or query shortcut |
| Root-task contamination | 18 | Remove the task before execution and link it to a same-stratum replacement |
| Route-level contamination | 5 | Keep the root task but block the affected route and its answer-bearing material |
| Restoration check | 23 | Reinsert only for sensitivity analysis; the full-system mean rises by 2.1 verified resolutions |
| Field | Content |
|---|---|
| Declaration identity | Claim identifier, statement version, Lean name, and source file |
| Environment | Lean, Mathlib, project dependencies, execution policy, and imports |
| Result | Compilation status, error category, runtime, and resource limit |
| Axiom audit | sorry / admit , new axioms, unsafe , and #print axioms |
| Semantic edge | Correspondence of natural-language objects, quantifiers, scope, degenerate cases, and direction |
| Composition edge | Parent claim, dependency subgraph, open obligations, and covered range |
| State condition | Repeated target runs | Stale returns | Recovery minutes | Unrelated withdrawals |
|---|---|---|---|---|
| No persistent state | 29 | 7 | 93 | 25 |
| Task graph only | 13 | 4 | 56 | 14 |
| Task and claim graphs | 4 | 0 | 34 | 5 |