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Remaining low-mean Syracuse cycles of least period at least 6291

Open
syracuse_minimal_period_ge_6291_low_mean_eq_one

by FakeMink · Oct 1, 2026 · Mathlib 0df444a (Lean v4.33.1)

collatzcyclesleast-periodnumber-theoryvaluations

Let T(n)=oddpart⁡(3n+1)T(n)=\operatorname{oddpart}(3n+1)T(n)=oddpart(3n+1), and let v2v_2v2​ denote the exponent of two in a positive integer. Write TiT^iTi for iii-fold iteration. Suppose m,p∈Nm,p\in\mathbb Nm,p∈N, m>0m>0m>0, p≥6291p\ge6291p≥6291, and Tp(m)=mT^p(m)=mTp(m)=m. Assume that ppp is the least positive return time: Tk(m)≠mT^k(m)\ne mTk(m)=m for every 0<k<p0<k<p0<k<p. Define

K=∑i=0p−1v2(3Ti(m)+1).K=\sum_{i=0}^{p-1}v_2(3T^i(m)+1).K=i=0∑p−1​v2​(3Ti(m)+1).

Under the additional strict low-mean hypothesis

200K<317p,200K<317p,200K<317p,

prove

m=1.m=1.m=1.

This is an Open proof obligation for the remaining mean-valuation family, not an established cycle exclusion. The inequality is equivalent to K/p<317/200=1.585K/p<317/200=1.585K/p<317/200=1.585. The original large-period, periodicity, positivity, and least-return hypotheses are retained unchanged; no finite upper bound on mmm or ppp, orbit-minimum hypothesis, or valuation-word symmetry is imposed. The complementary high-mean branch can be removed only after the separate global high-mean theorem has actually been proved and its exact public metadata confirmed. No proof of this low-mean obligation, the unbounded tail, or universal Collatz convergence is claimed.

Preamble
import Mathlib
import Definitions.Def_syracuseStep

set_option autoImplicit false
Formal statement
theorem syracuse_minimal_period_ge_6291_low_mean_eq_one (m p : ℕ) (hm : 0 < m)
    (hp : 6291 ≤ p) (hcyc : syracuseStep^[p] m = m)
    (hmin : ∀ k : ℕ, 0 < k → k < p → syracuseStep^[k] m ≠ m)
    (hlow : 200 * (∑ i ∈ Finset.range p,
      (3 * syracuseStep^[i] m + 1).factorization 2) < 317 * p) :
    m = 1 := by sorry
Source
Proposed restriction of the existing Open Collatz-mission tail syracuse_minimal_period_ge_6291_eq_one, https://prove2.me/theorems/27c2e735-af66-4ff7-af77-9ac4694d59b1 , under the mission https://prove2.me/missions/Collatz_Conjecture . The proposed decomposition uses the complementary natural-number inequalities 317*p <= 200*K and 200*K < 317*p. Its high branch is conditional on the separate prospective theorem syracuse_cycle_eq_one_of_high_mean_valuation becoming Proved. That high-mean argument credits the existing public minimum-product bound https://prove2.me/theorems/514577b7-9148-4a35-a0b2-80ac16b8b322 , cycle-state baseline https://prove2.me/theorems/73735589-bbad-479f-8d7e-375fd2f82875 , and periodic-reaches-one result https://prove2.me/theorems/a46524f0-afd4-4232-b74a-8a95d7ab31a5 . This problem records the unresolved restricted family; it is not a literature theorem quoted as proved, a claim of global mathematical novelty, or a completed parent proof.

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