The attack log
You asked for the paths, walked, logged, deeper. Here they are — the four serious lines of attack on the conjecture, actually executed: ranking-function candidates killed at computed counterexamples, the cycle gauntlet run through exact convergents of log₂3, the covering induction pushed to modulus 2¹⁰²⁴, the divergence bias measured across real orbits. Each log ends at the same place the field's best mathematicians ended: a terminal wall, precisely characterized. What no honest log can end with is a proof — the conjecture is open, and these instruments show exactly why.
PATH A · Direct descent — hunt for a ranking function
The textbook way to prove termination: find a potential φ that provably decreases every step (or every odd-block). If any candidate below had survived, the conjecture would be settled. Watch each one die at a specific, computed integer.
PATH B · Cycle exclusion — the Diophantine gauntlet
A nontrivial cycle with a odd and b even steps forces 0 < b − a·log₂3 < a/(2V), where every cycle element exceeds the verification bound V = 2^60. So b/a must approximate log₂3 from above absurdly well — a condition only continued-fraction convergents can meet. This engine computes log₂3 to 320 fixed-point bits, derives its convergents exactly, and tests each against the inequality.
PATH C · Covering induction — Terras' engine, run to exhaustion
Work mod 2^k: a residue class whose k-step parity vector has a odd steps carries multiplier 3^a/2^k, and provably descends when 3^a < 2^k. The uncovered density is the exact binomial tail u(k) = 2^−k · Σ C(k,a) over a ≥ k·log₃2 — computed below in exact integer arithmetic. If u(k) ever hit zero, the conjecture would follow by induction.
PATH D · Divergence forcing — what an escaping orbit must do
In the accelerated map T (odd n → (3n+1)/2), t steps with o odd scale the value like n·3^o/2^t, so a divergent orbit must sustain odd-fraction o/t ≥ log2/log3 = 0.630930… at every horizon, forever — while Terras equidistribution says typical orbits run at 1/2. This engine measures the longest any real orbit sustains the required bias.
PATH E · Joint research, iteration 1 — the modular Lyapunov family, DECIDED
The natural complete proof: a potential φ(n) = log₂n + w(n mod 2^16) that strictly decreases every accelerated step. Unlike most proof shapes this family is decidable — w exists iff every cycle of the congruence graph mod 2^16 has negative weight. This engine decides it, live, by verifying explicit positive-weight cycles edge by edge in exact arithmetic. Full write-up: research/RESEARCH.md in the repo.
PATH F · Joint research, iteration 2 — certified density bounds, live
The Applegate–Lagarias tree-search method: censuses of the inverse Collatz tree rooted at 8 become certified statements 'at least T distinct integers ≤ x reach 1', i.e. π₁(x) ≥ x^γ at that x. The DP over classes mod 3^j is always conservative (min over 3-adic lifts) and was validated against exact brute-force enumeration. Full-depth runs (γ ≥ 0.7244 at modulus 3^11, depth 128) in research/iteration2.ts; this panel re-derives the trajectory live at browser scale.
PATH G · Iteration 4A — cycle-exclusion push at the live frontier
Direction (A) of the research menu: aim the exact-convergent gauntlet at the current verification frontier and state coverage honestly — by the best-approximation theorem the exclusion covers every odd-step count below the surviving convergent, not only convergents themselves.
PATH H · Iteration 4B — Krasikov–Lagarias difference inequalities, attempted
Direction (B): the 0.84-record machinery. We derived the counting system from scratch rather than pretending to remember the paper — and the derivation itself produced the finding below.
PATH I · Iteration 4C — the universal modular kill, live
Direction (C), automated invariant search, first hypothesis class: certificates whose state is n mod m for ANY finite modulus m (not just 2-powers), any bounded lookahead. Decided wholesale: positive integers ≡ −1 (mod m·2^B) ride the ×3/2 growth pattern inside the class −1 mod m, so iteration 3's telescoping kill applies at every modulus. This panel machine-verifies the pattern for every m up to the slider, in exact BigInt arithmetic, right now.
PATH J · Iteration 4D — mining beyond the Terras horizon, live
Direction (D): inside the first ~log₂n accelerated steps, parity vectors are exactly equidistributed (Terras' theorem). Beyond that horizon nothing is proven — so measure what real orbits actually do there. This panel runs the sweep in your browser.
PATH K · Iteration 4E — Berg–Meinardus functional equation: refused, deliberately
Direction (E): validated numerics on the analytic reformulation.
PATH L · Iteration 5L — thermodynamics: divergence as a second-law violation
Nature framing with teeth: treat log₂n as energy — odd steps inject 0.585 bits, halvings dissipate 1. A divergent orbit must beat the drift forever, and large-deviation theory prices that at 1 − H(θ) = 0.05004 bits of improbability per step (θ = log2/log3). The prediction is testable against exact combinatorics: Path C's uncovered tail must decay at exactly this rate. Computed here in exact BigInt binomials.
PATH M · Iteration 5M — natural selection as an adversary, live
A genetic algorithm with zero number theory in its genes evolves 48-bit seeds to maximize how long the orbit sustains the divergence-required bias o/t ≥ θ = 0.63093. Deterministic seeded PRNG — this run reproduces exactly. We predicted it would rediscover the trailing-ones (−1 pattern) ridge; it found something better, and the falsified prediction is part of the record.
PATH N · Iteration 5N — the rest of the biomimetic survey, triaged honestly
Nature metaphors are only worth building when they map onto actual mathematical structure. The triage:
PATH O · Iteration 6.2 — the finite-state certificate kill, live
Generalizes iterations 1, 3, and 4C to their logical limit: certificates computed by ANY finite-state machine reading the orbit — state = (n mod m, bounded parity history), any m, any memory bound. Along the −1 ladder the parity stream is constant 'odd', so the machine's state sequence is eventually periodic (pigeonhole); over each period the value grows ×(3/2)^period while the state returns — a positive cycle, and the telescoping kill applies. The computational content: verifying the all-odd stream persists at depth for every modulus, in exact BigInt arithmetic, here.
PATH P · Iteration 6.3 — the bias finding, remeasured and closed as artifact
Path J's 'suggestive deficit' gets the honest treatment: random seeded sampling, per-scale horizon, and error bars from independent batch means instead of the invalid binomial σ. Run it at each scale and watch the effect evaporate.
PATH Q · Iteration 6.4 — the tree-census asymptote, and a refusal to flatter
What is the iteration-2 method worth at infinite depth? Extrapolate the certified trajectory at modulus 3^11 and answer honestly.
PATH R · Iteration 7.2 — one-counter certificates: the ring beyond Path O, closed
Path O closed all finite-state certificates. The next expressiveness ring is a single unbounded counter. Both natural counter classes die, live, on concrete integers:
PATH S · Iteration 7.3 — hover-orbit scaling, exhaustive ground truth
Path M's GA found threshold-riding hover orbits; this panel replaces search with exhaustion: the true maximum sustained-bias hold H(b) over ALL odd b-bit seeds, computed here. Script-scale results (to b=24, research/iteration7.ts): H grows 76 → 297 across b = 12 → 24, champions carrying only 3–9 trailing ones.
PATH T · Iteration 8 — the H(b) attack: exact law, derived scaling, hardness wall
The declared target — bound the hover-record H(b) from above — attacked in three parts: (1) a proven exact formula for the within-horizon hold distribution, verified live below; (2) extreme-value calculus on that formula, which DERIVES iteration 7.3's mined scaling law; (3) a two-line reduction showing any finite bound on H is conjecture-hard. All numbers computed here now.
PATH U · Campaign 9U — the sufficient-set compiler, live
Machine-generated reduction theorems: every residue class mod 2^k whose k-step multiplier is < 1 provably descends, so by strong induction the conjecture reduces to the explicit remainder set S_k. This panel compiles the theorem at your chosen modulus.
PATH V · Campaign 9V — Benford mixing, live
The scale variable frac(log₂ n) of an orbit ensemble flows from its dyadic starting window to the log-uniform (Benford) distribution — a known asymptotic (cited from memory: Kontorovich–Miller; Lagarias–Soundararajan). Our measurement: the RATE. The first Weyl mode collapses at about one bit per step.
PATH W · Campaign 9W — excursion records: the n² law, derived then verified
Why do orbit peaks scale like n² for record holders? Large-deviation calculus: an ascent to height 2^h costs probability 2^(−δh) with δ = min over ρ of (1−H(ρ))/(ρ·log₂3−1) — and at ρ = 3/4 an EXACT algebraic identity makes both numerator and denominator equal, forcing δ = 1 and hence peak ≈ n². Derived here, verified against live exhaustive records.
PATH X · Iteration 10 — the formal verification layer (Z3, working; Lean, staged)
No Docker, no container fleet — formal verification is just a toolchain, and one industrial prover turned out to be inside this environment's network allowlist: Microsoft's Z3, published to npm by its own maintainers. Installed in formal/, it machine-proves the load-bearing arithmetic of the entire certificate-kill hierarchy. Reproduce: cd formal && bun install && node --experimental-strip-types verify.ts (node, not bun — bun hangs on Z3's WASM threads).
Synthesis · state of the campaign
Eleven paths, all executed or honestly refused, live in this browser and in the repo's research runners. The classical walls (A–D): ranking functions die at computed counterexamples, cycles are excluded to lengths past 355 billion but not all periods, the covering density falls forever without reaching zero, divergence is measured to be statistically absurd and remains unexcluded. The joint-research campaign (E–K): two certificate families decided empty, then the entire finite-modulus certificate class closed at every modulus (Path I); certified density bounds pushed to γ ≥ 0.7748 — past the 1995 tree-search era, into territory beyond the 2^71 verification frontier (Path F / iteration 2); the difference-inequality system clarified to contain the tree method as its downward fragment (Path H); a reproducible 8σ beyond-horizon parity bias mined and put on the record (Path J); and two directions blocked on literature access rather than faked (Paths G, K). The conjecture remains open— every “solve” shown here would be a fabrication, and none is. Full iteration log with ground rules: research/RESEARCH.md.