BB(6) hunt
Machines / H-2

1RB0LF_0RC1RD_0LD0RA_1RC0RE_1RF---_1LA0LB

H-2Cryptid candidateChaotic Bell Class 2bbchallenge ↗Explorer

Where it stands

Cryptid candidate, parked at the observation

Halting hunt H-2 (740 line 362, Chaotic Bell Class 2), 2026-10-13: own exact accelerated model (work/h2model.py: k=4 macro machine, run-length tape, own prover of limited Diff rules with nested rule use) ran 362 to step 2.1182e62873 (86.1M loops, 80 rules, 6.06M rule applications) and 433 (same table from E) to 10^43681: no halt. The model matches direct simulation at every loop boundary to 2e7, tmsim at ~1e11 (both starts), sligocki qsim in 1,179 deep fingerprint comparisons to 10^254 (362) and 597 to 10^217 (433), its own k=8 variant to 10^600, and its rules on constructed tapes. It finds the upstream halter tm128 (this table from F) halting at step 81,366,596,481,702 (F,1). Dynamics: counter runs consumed 2 words per pass, parity decides the next layout each phase (Collatz-like lottery, ~10^0.073 steps per phase): cryptid-like for any nonhalting proof. Details: notes.md, 'Halting hunt: exact model (2026-10-13)'.

Observe
Deepen
Informal proof
Rocq
space-time diagram, first 10,000 steps from blank
The first 10,000 steps from a blank tape. Time runs down; white is 1.
About this picture

The standard picture (bbchallenge.org's Default view): each row is the whole tape at one step, time runs downward, and the head's path draws the pattern.

bbchallenge-defaultStart blankRows steps 0 → 10,000, top to bottomWindow cells −200..199, left to rightColors 1 0 or unvisited

Overview

In one sentence

No summary yet: no observe.json, and status.json gives no relation.

Status
Cryptid candidatehalting-hunt exact model: done, no halt · updated 2026-10-13Parked · Halting hunt H-2 (740 line 362, Chaotic Bell Class 2), 2026-10-13: own exact accelerated model (work/h2model.py: k=4 macro machine, run-length tape, own prover of limited Diff rules with nested rule use) ran 362 to step 2.1182e62873 (86.1M loops, 80 rules, 6.06M rule applications) and 433 (same table from E) to 10^43681: no halt.
idle since Oct 13 21:09 · status.json 2026-10-13
Class
Chaotic Bell Class 2
On the list
line 328 of BB6_holdouts_663.txt · historical 740 line 362
eqv ×1table ×2sim 1e15
Your calls on file 1
next
Optional: more lottery compute (cheap, ~2.6e4 orders of magnitude per hour at the end, slowing as sqrt(time)); 428 can run on the same model unchanged. No nonhalting work (cryptid-like).

Mechanism

No observation yet: no observe.json here. See notes.md.

Proof & checks

No proof work yet.

Files

machines/<tm>/: 3 entries · raw notes, status, scripts, images

namesizechanged
notes.md ↓10.0 KB2026-10-13 21:09
status.json ↓2.0 KB2026-10-13 21:08
work/41 items2026-10-13 21:07
status.json in full
{
 "tm": "1RB0LF_0RC1RD_0LD0RA_1RC0RE_1RF---_1LA0LB",
 "label": "H-2",
 "status": "CRYPTID_CANDIDATE",
 "stage": "halting-hunt exact model: done, no halt",
 "updated": "2026-10-13",
 "cryptid_flag": true,
 "reason": "Halting hunt H-2 (740 line 362, Chaotic Bell Class 2), 2026-10-13: own exact accelerated model (work/h2model.py: k=4 macro machine, run-length tape, own prover of limited Diff rules with nested rule use) ran 362 to step 2.1182e62873 (86.1M loops, 80 rules, 6.06M rule applications) and 433 (same table from E) to 10^43681: no halt. The model matches direct simulation at every loop boundary to 2e7, tmsim at ~1e11 (both starts), sligocki qsim in 1,179 deep fingerprint comparisons to 10^254 (362) and 597 to 10^217 (433), its own k=8 variant to 10^600, and its rules on constructed tapes. It finds the upstream halter tm128 (this table from F) halting at step 81,366,596,481,702 (F,1). Dynamics: counter runs consumed 2 words per pass, parity decides the next layout each phase (Collatz-like lottery, ~10^0.073 steps per phase): cryptid-like for any nonhalting proof. Details: notes.md, 'Halting hunt: exact model (2026-10-13)'.",
 "holdout_line_740": 362,
 "family": "same table as 433 (start E in 362's labels); RWLAccHaltv6.v tm128 is the table from F and halts",
 "hunt": {
  "date": "2026-10-13",
  "result": "no_halt_to_horizon",
  "horizon_362": "2.1182e62873 steps (exact final step in work/m362_k4.jsonl end line)",
  "horizon_433": ">= 10^43681.49 steps (run stopped at 20:37 for validation slots; last progress line in work/m433_k4.jsonl)",
  "engine": "work/h2model.py (k=4); cross-checked with sligocki qsim via work/h2q.py",
  "certificate_route_if_halt": "RWLAcc62_BigUint solve_halt' only for halts within run-length reach (~1e14 for tm128); deeper halts need a certified replay of the limited Diff rules (does not exist)"
 },
 "next": "Optional: more lottery compute (cheap, ~2.6e4 orders of magnitude per hour at the end, slowing as sqrt(time)); 428 can run on the same model unchanged. No nonhalting work (cryptid-like)."
}