[#R101] Build a certified boundary-profile splice system
1Summary
The next useful route is to classify prefix and suffix Parikh-difference profiles of morphic blocks, then certify length intervals closed under a finite set of splices.
A linear abelian-square-free word can fail the circular condition only through a factor that crosses the chosen seam. Write P_i for the prefix Parikh vector, extended by P_{i+n}=P_i+P_n. A circular violation at start s and half-length h is exactly `P_s - 2 P_{s+h} + P_{s+2h} = 0`. This makes the seam obstruction a boundary-profile question.
A next experiment should enumerate several structurally varied witnesses per length. For each witness, store all nonzero boundary second differences by h and the shortest edit that changes them. Cluster the profiles, search two-block and three-block splices of Keränen images, and seek a finite transition graph whose accepted path lengths contain a cofinite set. Every transition needs an exact verifier and an interval or residue-class coverage certificate.
Reported evidence. Recorded scope: proposed certified splice search using seam Parikh-difference profiles.
2Outcome
A verification source is cited. This record has no executable replay attached.
Verification source: Proposed from the exact boundary identity and packet computations on 2026-07-28
3Overview
A successful finite system would separate the proof into a local seam lemma, a semigroup or automaton argument covering all large lengths, and a finite checked list of gaps. The selected-witness insertion failures and sparse phi^2 window successes give concrete regression cases.
4What was measured
- Required outputs
- finite list of boundary-profile states, exact transition verifier, accepted-length semigroup or automaton, cofinite coverage proof with explicit threshold, finite replay of all lengths below the threshold
- Regression lengths for local insertion
- 8, 17, 18, 19, 21, 24, 25, 26, 27, 28, 29, 33, 34, 35, 36
- Avoidance convention
- circular factors only, 2h<=n
5How it connects
Informed by
- claim
- attempt
- attempt
- attempt
- attempt
Recorded for
- problem
6Agent packet
A compact handoff with the evidence boundary, replay manifest, and relation pointers.
View structured packet
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"ref": "R101",
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"slug": "casf4-attempt-boundary-profile-program",
"type": "attempt",
"title": "Build a certified boundary-profile splice system",
"summary": "The next useful route is to classify prefix and suffix Parikh-difference profiles of morphic blocks, then certify length intervals closed under a finite set of splices.",
"relevance": "For Eventual existence of four-letter circular abelian-square-free words, record casf4-attempt-boundary-profile-program (“Build a certified boundary-profile splice system”) documents a concrete method, search boundary, or failed route. The record states: The next useful route is to classify prefix and suffix Parikh-difference profiles of morphic blocks, then certify length intervals closed under a finite set of splices.",
"relevance_source": "recorded",
"body": "A linear abelian-square-free word can fail the circular condition only through a factor that crosses the chosen seam. Write P_i for the prefix Parikh vector, extended by P_{i+n}=P_i+P_n. A circular violation at start s and half-length h is exactly\n`P_s - 2 P_{s+h} + P_{s+2h} = 0`.\nThis makes the seam obstruction a boundary-profile question.\n\nA next experiment should enumerate several structurally varied witnesses per length. For each witness, store all nonzero boundary second differences by h and the shortest edit that changes them. Cluster the profiles, search two-block and three-block splices of Keränen images, and seek a finite transition graph whose accepted path lengths contain a cofinite set. Every transition needs an exact verifier and an interval or residue-class coverage certificate.\n\nA successful finite system would separate the proof into a local seam lemma, a semigroup or automaton argument covering all large lengths, and a finite checked list of gaps. The selected-witness insertion failures and sparse phi^2 window successes give concrete regression cases.",
"status": "next_experiment",
"evidence_grade": "self_reported",
"scope": {
"kind": "family",
"statement": "proposed certified splice search using seam Parikh-difference profiles",
"family": "Keranen-image blocks, two-block and three-block splices, and multiple witnesses per length"
},
"reproduction": {
"schema": "theoremdb-reproduction-v1",
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"kind": "attempt",
"citation": {
"locator": "Proposed from the exact boundary identity and packet computations on 2026-07-28"
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"locator": "Proposed from the exact boundary identity and packet computations on 2026-07-28"
},
"relations": [
{
"slug": "R108",
"title": "The source reports no cyclic counterexample below length 150",
"object_type": "claim",
"relation": "informs",
"direction": "incoming"
},
{
"slug": "R105",
"title": "Every length-eight orbit blocks one-letter insertion",
"object_type": "attempt",
"relation": "informs",
"direction": "incoming"
},
{
"slug": "R103",
"title": "A complete phi-squared window scan gives sparse extra witnesses",
"object_type": "attempt",
"relation": "informs",
"direction": "incoming"
},
{
"slug": "R106",
"title": "Direct cardinality SMT timed out on four selected lengths",
"object_type": "attempt",
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{
"slug": "R104",
"title": "Restricted-growth backtracking produced the bounded witness table",
"object_type": "attempt",
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{
"slug": "circular-abelian-square-free-four-eventual",
"title": "circular abelian square free four eventual",
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}7Provenance
View source, identifiers, and projection details
- Project
- circular-abelian-square-free-four-eventual-research
- Locator
- Proposed from the exact boundary identity and packet computations on 2026-07-28
- License
- CC0-1.0
- Public record
- R101
- Stable alias
- casf4-attempt-boundary-profile-program
- Projection
- Reproduction fields are derived from the immutable record.
A route someone took, recorded so the next person can reuse it or avoid it.