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Path to Proof

The Collatz conjecture reduces to two independent claims:

Two fronts toward proving the Collatz conjecture

Proved Results

A compact summary linking to full proof pages:

#ResultStatementStatus
1Affine Orbit Structuredest(n)=(3s/2ks)n+C\text{dest}(n) = (3^s/2^{k-s}) \cdot n + C within each subgroupProved
2Logarithmic EscapeSelf-chains bounded by logP(n)\log_P(n)Proved
3Bit Destructionβ(s)=1{slog23}>0\beta(s) = 1 - \{s \log_2 3\} > 0 alwaysProved
43-Adic Mixingord(3mod2B)=2B2\text{ord}(3 \bmod 2^B) = 2^{B-2}; transitions 98.7% independentProved
5Ascending EliminationAll ascending convergents give n<0n < 0Proved
6Gap=13 EliminationNo 13-step cycle (91 words checked)Proved
7Trivial Cycle IdentificationAll divisibility zeros produce n{1,2,4}n \in \{1, 2, 4\} onlyVerified (K30K \leq 30)

Front 1: No Cycles (~95%)

The proof reduces to a single convergent.

Convergent (S,E)(S, E)Gap ggMethodStatus
All ascendingnegativeC>0n<0C > 0 \Rightarrow n < 0Proved
(1,2)(1, 2), K=3K = 311Trivial cycle onlyProved
(5,8)(5, 8), K=13K = 1313130/91 words, complete enumerationProved
(41,65)(41, 65), K=106K = 1064.2×1017\sim 4.2 \times 10^{17}0 in all 2.5×10172.5 \times 10^{17} subsets (Rust MITM, 87 min)ELIMINATED
All S306S \geq 306>C(E1,S1)> C(E{-}1, S{-}1)log2(words)<log2(g)\log_2(\text{words}) < \log_2(g)Heuristic (needs uniformity bound)

The asymptotic argument. log2C(E1,S1)0.950E\log_2 C(E{-}1, S{-}1) \approx 0.950 \cdot E while log2gE\log_2 g \approx E. Since 0.950<10.950 < 1, the number of parity words grows exponentially slower than the gap for all convergents beyond (41,65)(41, 65). Even perfectly random sums cannot hit a multiple of gg.

The entire no-cycle proof reduces to one convergent: (S=41,E=65)(S = 41, E = 65), where g=19×29×763142958708379g = 19 \times 29 \times 763142958708379. The word/gap ratio is 0.60 — tantalizingly close but not yet rigorous.

Approaches to close this last gap:

  1. Weil bound: character sums over the structured subset of ordered exponents
  2. CRT independence: Tmod19T \bmod 19, Tmod29T \bmod 29, Tmodp3T \bmod p_3 are empirically independent; prove it
  3. Structural: extend the gap-13 argument using multiplicative orders mod the prime factors

Front 2: No Divergence (~30%)

What we have:

  • β(s)>0\beta(s) > 0 always (every drop destroys bits)
  • Roth: β(s)>c/s\beta(s) > c/s (bounded away from 0)
  • Mixing: set transitions nearly independent
  • Log Escape: can't camp in slow sets
  • "Almost all" nn converge (Terras-type)

The gap: Proving every nn has finite dropping time. This is equivalent to: the union of all dropping set residue classes covers every integer >1> 1.

Possible approaches:

  1. Prove mixing prevents systematic slow-set avoidance
  2. Find a Lyapunov function decreasing along every orbit
  3. Base-6 lattice covering argument
  4. Pillai conjecture: 2m3n|2^m - 3^n| \to \infty would give β>c\beta > c (constant)

Connections to Classical Mathematics

Our resultClassical connection
β(s)=1{slog23}\beta(s) = 1 - \{s \log_2 3\}Equidistribution (Weyl)
β(s)>c/s\beta(s) > c/sIrrationality measure (Roth)
Cycle gap =2E3S= 2^E - 3^SS-unit equations, Pillai
Divisibility obstruction on CCNew (from Collatz affine structure)
ord(3mod2B)=2B2\text{ord}(3 \bmod 2^B) = 2^{B-2}2-adic analysis
rad(2a3b)=6\text{rad}(2^a \cdot 3^b) = 6abc conjecture
"Almost all" convergeTerras (1976)

Open Questions

  1. Is there an algebraic proof that gCg \nmid C for all valid parity words when g>1g > 1? Would kill all cycles.
  2. Can the 3-adic mixing be promoted from statistical to deterministic? Would address divergence.
  3. Does the base-6 lattice give a covering argument? The modulus 2k2s6s2^{k-2s} \cdot 6^s unifies 2-adic and 3-adic views.
  4. Can the divisibility obstruction be verified for (S=41,E=65)(S=41, E=65)? Direct enumeration infeasible; needs algebraic or sampling approach.