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Status: pairwise-coprime case proved for all finite n; shared-factor C3/C4 certified
Date: 2026-08-15
Depends on: C1-THEOREM.md, C2-THEOREM.md
Claim boundary: Does not prove Erdős-Straus, López-all-primes, or DSC-P for unconstrained shared-prime clusters of arbitrary geometry. Closes the coprime-tower route and certifies small shared clusters.
Setup
Directly novel candidate. Active fixed-negative layers
with pullback moduli q_i > 1 and forbidden sets R_i as in C1. Let
by Theorem C1 (U_i = units mod q_i). Put Q = lcm(q_1,...,q_n).
Theorem CN-coprime (all finite n)
If gcd(q_i, q_j) = 1 for all i ≠ j, then a simultaneous reduced escape exists.
Proof
By C1, each S_i ≠ ∅. Choose a_i ∈ S_i. The system
has a unique solution mod Q = q_1···q_n by the Chinese Remainder Theorem. Moreover gcd(s,Q)=1. Hence s is reduced and avoids every R_i. QED.
Induction form. The case n=1 is C1. The case n=2 is C2-coprime. For n≥3, CRT against the product of the first n−1 moduli (inductively safe) with a_n ∈ S_n extends the escape.
Theorem CN-shared (certificates)
When the q_i share prime factors, compatibility conditions mod those primes are required.
Certificate C3 / C4 (tight, admissible)
See CN-SHARED-THEOREM.md. On the 73,814 admissible hard candidates through k ≤ 1500:
- tight
q ≤ 9triples:3,994,891checks, 0 failures; - the only shared-pair failures are
21complementaryq=3covers in the205family, all directly shadowed by layer10.
Sampled-r C3/C4 scans remain valid as samples. They are not a universal shared-factor theorem. Unrestricted complementary q=3 covers exist.
Obstruction pattern
Lift-room peels every layer with φ(q)/φ(d) > |R|. The totient-ratio lemma makes this automatic whenever d < q and |R| ≤ 1. The residual tight cluster is 3-adic. Complementary covers there are either non-admissible or ancestry-absorbed (205 → 10). A fully formal proof that every q=3 layer is an absorbed child of a q=1 anchor is the remaining shared-CN path.
Corollary — Coprime active cores are DSC-P complete
Any directly novel candidate whose active fixed-negative moduli are pairwise coprime is reduced-realizable:
- Character-shield extension (parent)
- Inactive fixed-negative layers safe by direct novelty
- CN-coprime simultaneous escape
- Fiber reverse (parent)
- Dirichlet → infinitely many exact-depth primes
Scoreboard
| Result | Status |
|---|---|
| C1 | Closed |
| C2-coprime | Closed |
| C2-shared | Certified 0-fail |
| CN-coprime (all n) | Closed |
| C3/C4 shared | Tight admissible 0-fail; unrestricted C2-shared false |
| 205-absorption | Closed (CN-SHARED-THEOREM.md) |
| Arbitrary shared CN | Open (remaining q=3 families) |
| Universal DSC-P | Open |
| López all primes | Open |
| Erdős-Straus | Open |
Next
- Formalize shared-factor CN via simultaneous projection of thin two-box pullbacks.
- Bound
|N^{act}|in the Class-C residual (parent census: median variable negative towers ~1). - If
|N^{act}|is uniformly bounded or generically pairwise-coprime, DSC-P collapses to closed theorems.