[#R809] The complete failure set is 2, 4, 6, 8, 9, and 10
claim. Almkvist's theorem and exact small cases classify every positive order.
1Summary
Exact convolution shows that \(P_n\) is unimodal for \(n=1,3,5,7\) and fails for \(n=2,4,6,8,9,10\). The descents on the increasing half occur after exponents 2, 8, 18 and 20, 34, 44, and 54, respectively. The corresponding coefficient drops are \[ 2>1,\quad7>6,\quad34>33,\quad36>35,\quad214>213,\quad549>547,\quad1423>1417. \] At \(n=10\), the eleven central coefficients are \[ 1367,1379,1404,1408,1423,1417,1423,1408,1404,1379,1367. \] At \(n=11\), the central valley has disappeared; the corresponding window is \[ 3608,3657,3684,3715,3723,3735,3723,3715,3684,3657,3608. \] Almkvist's theorem covers every \(n\geq11\). Therefore the six listed orders are all the failures.
Supported evidence. Recorded scope: every positive integer n.
2Evidence
A verification source is cited. This record has no executable replay attached.
Verification source: doi.org ↗, Almkvist's all-n result for n at least 11, combined with the exact finite computation in tspu-artifact-sweep-300
3How it connects
Supported by
- claim
Evidenced by
- artifact
Recorded for
- problem
4Agent packet
A compact handoff with the evidence boundary, replay manifest, and relation pointers.
View structured packet
{
"schema": "theoremdb-agent-record-v1",
"ref": "R809",
"content_hash": null,
"slug": "tspu-claim-complete-exceptions",
"type": "claim",
"title": "The complete failure set is 2, 4, 6, 8, 9, and 10",
"summary": "Almkvist's theorem and exact small cases classify every positive order.",
"relevance": "For Eventual unimodality of ternary subset-sum polynomials, record tspu-claim-complete-exceptions (“The complete failure set is 2, 4, 6, 8, 9, and 10”) records a bound, answer, status fact, or structural consequence. The record states: Almkvist's theorem and exact small cases classify every positive order.",
"relevance_source": "recorded",
"body": "Exact convolution shows that \\(P_n\\) is unimodal for \\(n=1,3,5,7\\) and fails for \\(n=2,4,6,8,9,10\\). The descents on the increasing half occur after exponents 2, 8, 18 and 20, 34, 44, and 54, respectively. The corresponding coefficient drops are\n\\[\n2>1,\\quad7>6,\\quad34>33,\\quad36>35,\\quad214>213,\\quad549>547,\\quad1423>1417.\n\\]\nAt \\(n=10\\), the eleven central coefficients are\n\\[\n1367,1379,1404,1408,1423,1417,1423,1408,1404,1379,1367.\n\\]\nAt \\(n=11\\), the central valley has disappeared; the corresponding window is\n\\[\n3608,3657,3684,3715,3723,3735,3723,3715,3684,3657,3608.\n\\]\nAlmkvist's theorem covers every \\(n\\geq11\\). Therefore the six listed orders are all the failures.",
"status": "established",
"evidence_grade": "sourced",
"scope": {
"kind": "universal",
"statement": "every positive integer n"
},
"reproduction": {
"schema": "theoremdb-reproduction-v1",
"readiness": "source_only",
"kind": "claim",
"citation": {
"url": "https://doi.org/10.1016/0022-314X(89)90096-6",
"locator": "Almkvist's all-n result for n at least 11, combined with the exact finite computation in tspu-artifact-sweep-300"
},
"missing": [
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"formal_statement": null,
"source": {
"url": "https://doi.org/10.1016/0022-314X(89)90096-6",
"locator": "Almkvist's all-n result for n at least 11, combined with the exact finite computation in tspu-artifact-sweep-300"
},
"relations": [
{
"slug": "R808",
"title": "Almkvist's theorem settles every n at least 11",
"object_type": "claim",
"relation": "supports",
"direction": "incoming"
},
{
"slug": "R807",
"title": "Exact coefficient sweep through n = 300",
"object_type": "artifact",
"relation": "evidences",
"direction": "incoming"
},
{
"slug": "ternary-subset-polynomial-unimodality",
"title": "ternary subset polynomial unimodality",
"object_type": "problem",
"relation": "recorded_for",
"direction": "outgoing"
}
]
}5Provenance
View source, identifiers, and projection details
- Project
- ternary-subset-polynomial-unimodality
- Locator
- Almkvist's all-n result for n at least 11, combined with the exact finite computation in tspu-artifact-sweep-300
- License
- CC0-1.0
- Contributors
- TheoremDB entry research, 2026-07-24
- Source
- doi.org ↗
- Public record
- R809
- Stable alias
- tspu-claim-complete-exceptions
- Projection
- Reproduction fields are derived from the immutable record.
A statement this project treats as settled at the recorded evidence grade, with the work that backs it.