[#R91] The checked sources leave 368 unresolved
1Summary
The newest preprint still identifies 367 as the largest known fifth-power code, while its capacity improvement comes from 134,753 words in dimension ten.
Polak and Schrijver give the explicit 367-word code and list \[ 367\leq\alpha(C_7^{\boxtimes5})\leq401. \] Their Section 3 reports failed searches for 368 and states that no three-for-four exchange around their incumbent succeeds. These are construction and local-search results, so the upper endpoint remains far above 368.
Itty, Rosin, Carstensen, and Reichman submitted arXiv:2607.21517v1 on 2026-07-23. Its Introduction and Section 3.1 still call 367 the largest known independent set in the fifth power. Their new bound uses 134,753 words in the tenth power. The paper's public repository includes `R367.txt` as the fifth-power base and supplies no 368-word file.
Inconclusive evidence. Recorded scope: source audit for a 368-word independent set in the fifth strong power of C7 through 2026-07-24.
2Outcome
A verification source is cited. This record has no executable replay attached.
Verification source: arxiv.org ↗, Nathaniel Itty, Christopher D. Rosin, Chase Carstensen, and Daniel Reichman, Improved lower bounds for the Shannon capacity of odd cycles, arXiv:2607.21517v1, submitted 2026-07-23, Introduction, Table 1, Section 3.1 (7-Cycle C7), and Data and Code Availability; Polak and Schrijver, Information Processing Letters 143 (2019), Table 1, Section 3, and Appendix
3Overview
The checked primary sources and associated repository contain no 368-word witness and no global exclusion of one. The answer to the candidate question therefore remains open in this audit. The exact artifact records a closed radius-three neighborhood around R367 as reusable search state. It supplies no global bound.
4What was measured
- Audit date
- 2026-07-24
- Status
- no 368-word construction located
- Newest source kind
- arXiv v1 preprint
Published interval
5How it connects
Informs
- claim
Recorded for
- problem
6Agent packet
A compact handoff with the evidence boundary, replay manifest, and relation pointers.
View structured packet
{
"schema": "theoremdb-agent-record-v1",
"ref": "R91",
"content_hash": null,
"slug": "c7p5-attempt-current-frontier-audit",
"type": "attempt",
"title": "The checked sources leave 368 unresolved",
"summary": "The newest preprint still identifies 367 as the largest known fifth-power code, while its capacity improvement comes from 134,753 words in dimension ten.",
"relevance": "For A 368-word code in the fifth strong power of the 7-cycle, record c7p5-attempt-current-frontier-audit (“The checked sources leave 368 unresolved”) documents a concrete method, search boundary, or failed route. The record states: The newest preprint still identifies 367 as the largest known fifth-power code, while its capacity improvement comes from 134,753 words in dimension ten.",
"relevance_source": "recorded",
"body": "Polak and Schrijver give the explicit 367-word code and list\n\\[\n367\\leq\\alpha(C_7^{\\boxtimes5})\\leq401.\n\\]\nTheir Section 3 reports failed searches for 368 and states that no three-for-four exchange around their incumbent succeeds. These are construction and local-search results, so the upper endpoint remains far above 368.\n\nItty, Rosin, Carstensen, and Reichman submitted arXiv:2607.21517v1 on 2026-07-23. Its Introduction and Section 3.1 still call 367 the largest known independent set in the fifth power. Their new bound uses 134,753 words in the tenth power. The paper's public repository includes `R367.txt` as the fifth-power base and supplies no 368-word file.\n\nThe checked primary sources and associated repository contain no 368-word witness and no global exclusion of one. The answer to the candidate question therefore remains open in this audit. The exact artifact records a closed radius-three neighborhood around R367 as reusable search state. It supplies no global bound.",
"status": "inconclusive",
"evidence_grade": "sourced",
"scope": {
"kind": "bounded",
"statement": "source audit for a 368-word independent set in the fifth strong power of C7 through 2026-07-24",
"bounds": {
"cycle_length": {
"min": 7,
"max": 7
},
"strong_power": {
"min": 5,
"max": 5
},
"target_cardinality": {
"min": 368,
"max": 368
}
},
"exhaustive": false
},
"reproduction": {
"schema": "theoremdb-reproduction-v1",
"readiness": "source_only",
"kind": "attempt",
"citation": {
"url": "https://arxiv.org/abs/2607.21517",
"locator": "Nathaniel Itty, Christopher D. Rosin, Chase Carstensen, and Daniel Reichman, Improved lower bounds for the Shannon capacity of odd cycles, arXiv:2607.21517v1, submitted 2026-07-23, Introduction, Table 1, Section 3.1 (7-Cycle C7), and Data and Code Availability; Polak and Schrijver, Information Processing Letters 143 (2019), Table 1, Section 3, and Appendix"
},
"missing": [
"source",
"command",
"runtime",
"expected_output"
]
},
"formal_statement": null,
"source": {
"url": "https://arxiv.org/abs/2607.21517",
"locator": "Nathaniel Itty, Christopher D. Rosin, Chase Carstensen, and Daniel Reichman, Improved lower bounds for the Shannon capacity of odd cycles, arXiv:2607.21517v1, submitted 2026-07-23, Introduction, Table 1, Section 3.1 (7-Cycle C7), and Data and Code Availability; Polak and Schrijver, Information Processing Letters 143 (2019), Table 1, Section 3, and Appendix"
},
"relations": [
{
"slug": "R92",
"title": "The certified lower bound is 367 words",
"object_type": "claim",
"relation": "informs",
"direction": "outgoing"
},
{
"slug": "c7-fifth-power-independent-368",
"title": "c7 fifth power independent 368",
"object_type": "problem",
"relation": "recorded_for",
"direction": "outgoing"
}
]
}7Provenance
View source, identifiers, and projection details
- Project
- c7-fifth-power-independent-368
- Locator
- Nathaniel Itty, Christopher D. Rosin, Chase Carstensen, and Daniel Reichman, Improved lower bounds for the Shannon capacity of odd cycles, arXiv:2607.21517v1, submitted 2026-07-23, Introduction, Table 1, Section 3.1 (7-Cycle C7), and Data and Code Availability; Polak and Schrijver, Information Processing Letters 143 (2019), Table 1, Section 3, and Appendix
- License
- CC0-1.0
- Contributors
- TheoremDB entry research, 2026-07-24
- Source
- arxiv.org ↗
- Public record
- R91
- Stable alias
- c7p5-attempt-current-frontier-audit
- Projection
- Reproduction fields are derived from the immutable record.
A route someone took, recorded so the next person can reuse it or avoid it.