BB(6) hunt
Machines / W6-4

1RB0LE_1RC1RB_1LD0RE_1LA1LC_1RB0LF_0LC---

W6-4ParkedChaotic Bell Class 1bbchallenge ↗Explorer

Where it stands

Parked at the observation

Observe + halting go/no-go done (about 1 h 20 min). The machine is ChaoticBell1Halt.v TM13's table renamed (ours A,B,C,D,E,F = TM13 D,A,B,C,E,F, no mirror), started in TM13's D; all TM13 lemmas hold verbatim (26 rules + the halt window validated 40/40 each from random instances).

Read the full status

An untrusted Python port of ccz181078's certified executor CBSim reproduces the upstream halts exactly (TM13 at tick 64,832, TM7 at 65,400) and matches direct simulation for 4,000 ticks (21,071,295 steps). From our start it runs 16,551,000 ticks (165x ccz181078's 100,000) with no halt; the same table from 602's start runs 10,000,000 ticks and from 299's start 7,627,000 ticks, no halt. NO-GO for the HALT route at this budget; no nonhalting attempt (plan). New: after ~4e5 ticks every run enters a regular phase, a left stack of PL(n)^k_n (n = 0..~80, k ~1e31) whose counts fall ~5x per two levels with small remainders (k_n - 5 k_(n+2) in -89..178); the executor eats it from the near end at ~1 level per 3e6 ticks.

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

TM13's table (ChaoticBell1Halt.v) from TM13's D: CB1 bell; certified-executor port finds no halt in 16.5M ticks.

Status
Parkedobserving · updated 2026-10-14Not blocking · Stuck at the observing stage. Answer Q1–Q3 whenever; a “no” redirects the work.
idle since Oct 14 16:43 (44 h ago) · status.json 2026-10-14
Class
Chaotic Bell Class 1ours: Chaotic Bell Class 1 (sheet) · ours adds: ChaoticBell1Halt.v TM13's table (renamed), started in TM13's D · med confidence
On the list
line 373 of BB6_holdouts_663.txt · historical 740 line 412 · observe.json rank #412
eqv ×2table ×3sim 1e13
Your calls on file 3
priority call (answered)
No halt in 16.5M executor ticks. Park the CB1 cluster (412, 602, 299), or fund one 2 h stage for an exact level accelerator of the late PL stack (cryptid stop if the per-level map branches on remainders mod 5)?
parked
Dennis 2026-10-14: park
2026-10-14 · park
W6-4's halting go/no-go found no halt at 165x upstream's budget: park the CB1 cluster (412, 602, 299), or fund one 2 h stage?

Mechanism

How it works: 3 notes
  • Same table as ChaoticBell1Halt.v TM13 (ours A,B,C,D,E,F = TM13 D,A,B,C,E,F; no mirror): our blank start is TM13 started in D. All TM13 lemmas hold verbatim; 26 rules + the halt window pass 40/40 random instances here.
  • A bell over digits D n = 1^(2n+1) 00: B> 0100 sweeps right (D n -> S n = 1(01)^(n+1)), <C 1 sweeps back. Each 111 on the left is one call (sweep to the right end, append 100 100); PL blocks replay calls; the far left turns the head (over1/over2). Direct sim: no halt to 1e9 (sheet: 1e13); left-end tapes are clean D-digit lists.
  • Port of ccz181078's certified executor (CBSim): reproduces TM13's halt (tick 64,832) and TM7's (65,400), matches direct sim for 4,000 ticks (21.1M steps). Our start: no halt in 16,551,000 ticks; 602's start: none in 10,000,000; 299's: none in 7,627,000. After ~4e5 ticks the run turns regular: a stack of PL(n)^k_n, n = 0,1,2,..., counts ~1e31 falling ~5x per two levels, small remainders.

Figures for Checkpoint A

Fig 1 · bbchallenge Default view, 10,000 stepsviewer ↗

Orientation: the head sweeps the whole tape; the right edge moves out a little per sweep.

bbchallenge Default view, 10,000 steps
bbchallenge-defaultStart blankRows every step 0..9,999Window cells -200..199, 1 px = 1 cellColors 1 0 or unvisited head (last move right/left)
Rows: squeezed into 500 px by the site's bilinear filter (about one sample per 20 steps)
Fig 2 · Every 10^6 steps up to 10^9Q2

Rows are snapshots 10^6 steps apart. Compare the fixed left edge with the right edge.

Every 10^6 steps up to 10^9
bbchallenge-defaultStart blankRows every 1,000,000 stepsWindow cells -518..36,471, 1 px = 16 cellsColors 1 0 or unvisited head (last move right/left)
Rows: 0..1,000,000,000 (1,001 rows) · Window: every 16th cell sampled; the head is kept
Fig 3 · Close-up: two calls from a constructed tapeQ1

Start: two 111 groups left of the head. Follow each sweep to the right end and back.

Close-up: two calls from a constructed tape
bbchallenge-exploreStart constructed: 0∞ 1 111 111 0101 <C 1 111 00 11111 00 1 00 0∞Rows every step, 0..180Window cells -13..20, 1 px = 0.1 cellsColors 1 0
Rows: 181 rows, 10 px per step · Window: 10 px per cell · Colors: head coloured by state: A red, B orange, C blue, D green, E magenta, F cyan
More figures (1)Fig 4: Explore view: the first 50 steps
Fig 4 · Explore view: the first 50 stepsviewer ↗

State colours: the first far-left turns (over1/over2) and the first appended digits.

Explore view: the first 50 steps
bbchallenge-exploreStart blankRows every step 0..49Window cells -40..39, 1 px = 0.1 cellsColors 1 0
Rows: the site's 800x500 Explore view, 10 px per step · Window: 10 px per cell · Colors: head coloured by state: A red, B orange, C blue, D green, E magenta, F cyan
Rules (28/28 validated)exact tape rewrites the proof will formalize, each re-checked by simulation
rulefrom ⟶ tocasesstepschecked
moveR
l B> 0100 12n+1 00 r
⟶ l 1(01)n+1 B> 0100 r
all parameters >= 0, any l, r—✓40/40
moveL
l 1(01)n+1 <C 1 r
⟶ l <C 1 12n+1 00 r
all parameters >= 0, any l, r—✓40/40
emptyR
l B> 0100 0∞
⟶ l <C 1 100 100 0∞
right context is 0^inf—✓40/40
blank
l B> 0100 000 r
⟶ l <C 1 100 100 r
all parameters >= 0, any l, r—✓40/40
restartL
l 111 (01)b+1 <C 1 r
⟶ l (01)b+1 B> 0100 r
all parameters >= 0, any l, r—✓40/40
moveJ
l 1(01)n+1 <D 100 r
⟶ l <C 1 12n+3 00 r
all parameters >= 0, any l, r—✓40/40
restartJ
l 111 (01)b <D 100 r
⟶ l (01)b+1 B> 0100 r
all parameters >= 0, any l, r—✓40/40
finishPL
l 101 10 (01)b+1 <C 1 r
⟶ l <D 100 12b+3 00 r
all parameters >= 0, any l, r—✓40/40
collide
l B> 0100 10 100 100 r
⟶ l <D 100 11111 00 10 r
all parameters >= 0, any l, r—✓40/40
pairR
l B> 0100 10 (12n+5 00)2 r
⟶ l 101 101 12n (01)n+4 B> 0100 10 r
all parameters >= 0, any l, r—✓40/40
even
l B> 0100 12n+2 00 r
⟶ l <C 1 12n+3 00 10 r
all parameters >= 0, any l, r—✓40/40
over2
0∞ 11 (01)b+1 <C 1 r
⟶ 0∞ 12b+2 0101 B> 0100 1 r
left context is 0^inf; b >= 0—✓40/40
over1
0∞ 1 (01)b+1 <C 1 12n+1 00 r
⟶ 0∞ 12b (01)n+2 B> 0100 10 r
left context is 0^inf (far left end); b, n >= 0—✓40/40
collision
l 101100 <C 1 r
⟶ l <D 100 1111 r
all parameters >= 0, any l, r—✓40/40
turnB
l 11 <C 1 12n+1 00 r
⟶ l (01)n+1 B> 0100 r
all parameters >= 0, any l, r—✓40/40
defect0
l B> 0100 10 100 1 12m 0 r
⟶ l <D 100 1111 12m+1 00 1 r
all parameters >= 0, any l, r—✓40/40
defect1
l B> 0100 10 11100 1 12m 0 r
⟶ l <C 1 100 100 12m+3 00 1 r
all parameters >= 0, any l, r—✓40/40
defect2
l B> 0100 10 12n+5 00 1 12m 0 r
⟶ l 101 101 12n (01)m+2 B> 0100 1 r
all parameters >= 0, any l, r—✓40/40
defectBlank0
l B> 0100 10 100 00 r
⟶ l 101 1001 B> 0100 r
all parameters >= 0, any l, r—✓40/40
defectBlankS
l B> 0100 10 12n+3 00 00 r
⟶ l 101 101 1 12n 01 B> 0100 r
all parameters >= 0, any l, r—✓40/40
paired
l B> 0100 (10)2k 12n+1 00 r
⟶ l 101 (1011)k (01)n B> 0100 r
k >= 1, n >= 0—✓40/40
calls
l (111)h (01)b+1 <C 1 D(v1)..D(vk) 0∞
⟶ l (01)b+1 <C 1 D(v1)..D(vk) (100)2h 0∞
h >= 1, b >= 0, any digit list; right context 0^inf—✓40/40
scanR
l B> 01 (11)k r
⟶ l (01)k B> 01 r
all parameters >= 0, any l, r—✓40/40
scanB
l (10)k <C r
⟶ l <C (11)k r
all parameters >= 0, any l, r—✓40/40
scanC
l (01)k <D r
⟶ l <D (11)k r
all parameters >= 0, any l, r—✓40/40
scanPair
l B> 01 (0101)k r
⟶ l (1011)k B> 01 r
all parameters >= 0, any l, r—✓40/40
halt_window
l 11100 <C r halts (C reads 0
⟶ 1LD, ..., F reads 1 = ---)
any l, r—✓40/40
executor = machine
blank, our A (= TM13 from D)
⟶ each of the first 4,000 executor configurations, in order
Python port of CBSim; exact tape match at every tick21,071,295 direct steps✓4000/4000
Compressed historythe tape as left-end visits (direct sim): 0∞ <X D(n1) D(n2) ... D(nk) 0∞, D n = 12n+1 00 at 30 moments: where the rules are read off
left-end visits (direct sim): 0∞ <X D(n1) D(n2) ... D(nk) 0∞, D n = 12n+1 00
stepspandigits kmax digitnon-digit 1-runs
74100
8,34414439100
15,4061722430
25,5042252491
61,04434148170
91,57040667100
172,07752352120
292,22270093140
325,715764115130
416,08080574191
881,6761,246209150
1,424,5551,566255160
2,161,4931,914293200
3,572,5592,456399181
5,520,9183,076517220
6,836,1343,165305210
10,850,0733,973392211
11,038,7534,040415211
17,619,6235,055524210
35,574,7207,5271,140241
56,207,0689,4271,432240
69,081,7989,852983260
109,402,36012,3561,255260
170,969,38915,4871,608270
218,840,41418,5012,810260
220,347,77518,5942,855320
344,466,41523,3083,611240
537,353,46829,1254,510290
1,032,545,05937,7323,707281
1,613,253,74747,1464,609330
spanlast 47,146
47,146471.6e9log xstep 7: span = 4step 8344: span = 144step 15406: span = 172step 25504: span = 225step 61044: span = 341step 91570: span = 406step 172077: span = 523step 292222: span = 700step 325715: span = 764step 416080: span = 805step 881676: span = 1246step 1424555: span = 1566step 2161493: span = 1914step 3572559: span = 2456step 5520918: span = 3076step 6836134: span = 3165step 10850073: span = 3973step 11038753: span = 4040step 17619623: span = 5055step 35574720: span = 7527step 56207068: span = 9427step 69081798: span = 9852step 109402360: span = 12356step 170969389: span = 15487step 218840414: span = 18501step 220347775: span = 18594step 344466415: span = 23308step 537353468: span = 29125step 1032545059: span = 37732step 1613253747: span = 47146
digits klast 4,609
4,609171.6e9log xstep 7: digits k = 1step 8344: digits k = 39step 15406: digits k = 24step 25504: digits k = 24step 61044: digits k = 48step 91570: digits k = 67step 172077: digits k = 52step 292222: digits k = 93step 325715: digits k = 115step 416080: digits k = 74step 881676: digits k = 209step 1424555: digits k = 255step 2161493: digits k = 293step 3572559: digits k = 399step 5520918: digits k = 517step 6836134: digits k = 305step 10850073: digits k = 392step 11038753: digits k = 415step 17619623: digits k = 524step 35574720: digits k = 1140step 56207068: digits k = 1432step 69081798: digits k = 983step 109402360: digits k = 1255step 170969389: digits k = 1608step 218840414: digits k = 2810step 220347775: digits k = 2855step 344466415: digits k = 3611step 537353468: digits k = 4510step 1032545059: digits k = 3707step 1613253747: digits k = 4609
max digitlast 33
33071.6e9log xstep 7: max digit = 0step 8344: max digit = 10step 15406: max digit = 3step 25504: max digit = 9step 61044: max digit = 17step 91570: max digit = 10step 172077: max digit = 12step 292222: max digit = 14step 325715: max digit = 13step 416080: max digit = 19step 881676: max digit = 15step 1424555: max digit = 16step 2161493: max digit = 20step 3572559: max digit = 18step 5520918: max digit = 22step 6836134: max digit = 21step 10850073: max digit = 21step 11038753: max digit = 21step 17619623: max digit = 21step 35574720: max digit = 24step 56207068: max digit = 24step 69081798: max digit = 26step 109402360: max digit = 26step 170969389: max digit = 27step 218840414: max digit = 26step 220347775: max digit = 32step 344466415: max digit = 24step 537353468: max digit = 29step 1032545059: max digit = 28step 1613253747: max digit = 33
non-digit 1-runslast 0
1071.6e9log xstep 7: non-digit 1-runs = 0step 8344: non-digit 1-runs = 0step 15406: non-digit 1-runs = 0step 25504: non-digit 1-runs = 1step 61044: non-digit 1-runs = 0step 91570: non-digit 1-runs = 0step 172077: non-digit 1-runs = 0step 292222: non-digit 1-runs = 0step 325715: non-digit 1-runs = 0step 416080: non-digit 1-runs = 1step 881676: non-digit 1-runs = 0step 1424555: non-digit 1-runs = 0step 2161493: non-digit 1-runs = 0step 3572559: non-digit 1-runs = 1step 5520918: non-digit 1-runs = 0step 6836134: non-digit 1-runs = 0step 10850073: non-digit 1-runs = 1step 11038753: non-digit 1-runs = 1step 17619623: non-digit 1-runs = 0step 35574720: non-digit 1-runs = 1step 56207068: non-digit 1-runs = 0step 69081798: non-digit 1-runs = 0step 109402360: non-digit 1-runs = 0step 170969389: non-digit 1-runs = 0step 218840414: non-digit 1-runs = 0step 220347775: non-digit 1-runs = 0step 344466415: non-digit 1-runs = 0step 537353468: non-digit 1-runs = 0step 1032545059: non-digit 1-runs = 1step 1613253747: non-digit 1-runs = 0
Template comparisonChaoticBell1Halt.v TM13: partly applies · the nearest solved proof, what carries over, and the transitions that differ
01
A1RB0LE
B1RC1RB
C1LD0RE
D1LA1LC
E1RB0LF
F0LC---
file
ChaoticBell1Halt.v ⚠ not at pin
module
TM13
machine
1RB1RA_1LC0RE_1LD1LB_1RA0LE_1RA0LF_0LB--- (8 transitions apart)
diff
same table renamed (ours A,B,C,D,E,F = TM13 D,A,B,C,E,F; no mirror); only the start differs (ours = TM13 from D)
note
All TM13 lemmas (scan*, right, left, blank, even, restart, overflow1/2, collision, leftJ, turnB, turnJ, finishP, defect*, paired, halt_window, core) are about the table only and hold here after renaming B->A, C->B, D->C. A HALT .v = the CB1/CBMacros/CBSim modules with the state letters renamed, our TM string, check_spec with fuel above the halting tick. That needs a halt, which the port did not find.
Proof strategy & riskshow the formal proof will go · 3 risks to watch

HALT route by the certified executor: no halt in 16.5M ticks (165x). If funded: an exact per-level map for the late PL stack, iterated to the bottom (~80 levels, ~2e8 ticks); cryptid stop on residue branching.

  • ▲ccz181078 very likely ran the same executor on the whole class and kept only TM7/TM13; our 100x+ runs agree that these starts do not halt early.
  • ▲The late phase looks like division by 5 with small remainders: a cryptid sign; a fitted law may branch on residues.
  • ▲The Python port only predicts; a kill would still need the Coq check_spec run (one coqc) after a halt.
Stats & provenance2·109 steps simulated · 47,146 cells · the status in full · files
simulated
2·109 steps
tape
47,146 cells · 22,051 nonzeros
growth
direct: span ~ sqrt(steps) (37,750 at 1.03e9; 47,146 at 1.6e9). Executor: 10^31 cells at 4.2e5 ticks, then ~10^33 to 1.65e7 ticks; the PL stack is eaten ~1 level per 3e6 ticks
status now
Observe + halting go/no-go done (about 1 h 20 min). The machine is ChaoticBell1Halt.v TM13's table renamed (ours A,B,C,D,E,F = TM13 D,A,B,C,E,F, no mirror), started in TM13's D; all TM13 lemmas hold verbatim (26 rules + the halt window validated 40/40 each from random instances). An untrusted Python port of ccz181078's certified executor CBSim reproduces the upstream halts exactly (TM13 at tick 64,832, TM7 at 65,400) and matches direct simulation for 4,000 ticks (21,071,295 steps). From our start it runs 16,551,000 ticks (165x ccz181078's 100,000) with no halt; the same table from 602's start runs 10,000,000 ticks and from 299's start 7,627,000 ticks, no halt. NO-GO for the HALT route at this budget; no nonhalting attempt (plan). New: after ~4e5 ticks every run enters a regular phase, a left stack of PL(n)^k_n (n = 0..~80, k ~1e31) whose counts fall ~5x per two levels with small remainders (k_n - 5 k_(n+2) in -89..178); the executor eats it from the near end at ~1 level per 3e6 ticks. (status.json, 2026-10-14)
observer's note
Rules exact (26/26 validated). Halting go/no-go: NO-GO, the certified-executor port finds no halt in 16,551,000 ticks from our start (602's start: 1e7; 299's: 7,627,000). Nonhalting not attempted (plan); the late phase is a regular PL stack with a /5-with-remainder look.
files
observe.json · notes.md · status.json

Proof & checks

No proof work yet.

Files

machines/<tm>/: 6 entries · raw notes, status, scripts, images

namesizechanged
notes.md ↓12 KB2026-10-14 15:10
status.json ↓3.1 KB2026-10-14 16:43
observe.json ↓17 KB2026-10-14 15:10
decisions/1 item2026-10-14 16:43
img/5 items2026-10-14 14:06
work/33 items2026-10-14 15:09
status.json in full
{
 "tm": "1RB0LE_1RC1RB_1LD0RE_1LA1LC_1RB0LF_0LC---",
 "label": "W6-4",
 "status": "STUCK",
 "stage": "observe",
 "updated": "2026-10-14",
 "confidence": "med",
 "reason": "Observe + halting go/no-go done (about 1 h 20 min). The machine is ChaoticBell1Halt.v TM13's table renamed (ours A,B,C,D,E,F = TM13 D,A,B,C,E,F, no mirror), started in TM13's D; all TM13 lemmas hold verbatim (26 rules + the halt window validated 40/40 each from random instances). An untrusted Python port of ccz181078's certified executor CBSim reproduces the upstream halts exactly (TM13 at tick 64,832, TM7 at 65,400) and matches direct simulation for 4,000 ticks (21,071,295 steps). From our start it runs 16,551,000 ticks (165x ccz181078's 100,000) with no halt; the same table from 602's start runs 10,000,000 ticks and from 299's start 7,627,000 ticks, no halt. NO-GO for the HALT route at this budget; no nonhalting attempt (plan). New: after ~4e5 ticks every run enters a regular phase, a left stack of PL(n)^k_n (n = 0..~80, k ~1e31) whose counts fall ~5x per two levels with small remainders (k_n - 5 k_(n+2) in -89..178); the executor eats it from the near end at ~1 level per 3e6 ticks.",
 "siblings": [
  "1RB0LE_1RC1RA_1LD0RE_1LA1LD_1LD0RF_0RA---",
  "1RB1RD_1LC0RE_1LD1LC_1RA0LE_1LC0RF_0RD---"
 ],
 "sibling_note": "Same table (canon over all starts and the mirror): 299 = TM13 from B (mirrored), 602 = TM13 from C (mirrored); our start C and D give them. Our start B = TM13 itself (halts, upstream). eqv-1590 partner of 412: 1RB0LE_1RC1RB_1LD0RA_1LF1LC_0LC---_1RB0LA (= TM13 from E, not on the 740 list). 338, 577, 730 are not this table: their eqv members are TM7 from B, D (and F), C; cousins, not run here.",
 "holdout_line_740": 412,
 "upstream": "verify/ChaoticBell1Halt.v (ccz181078, busycoq BB6 HEAD cdaf693) proves TM13 and TM7 halting from A; 412 itself is in no upstream file. No claim in data/discord or data/sheet (results row: class only; direct-simulation sheet: run to 1e13 without a halt).",
 "template": "verify/ChaoticBell1Halt.v Module TM13 (+ CB1, CBMacros, CBSim): rules apply verbatim after renaming; only the start differs",
 "executor_runs": {
  "port": "work/cbsim_fast2.py (untrusted Python transcription of CBSim; checks: upstream halt ticks, 4,000-tick direct-sim match)",
  "TM13_from_D_412": {
   "ticks": 16551000,
   "halted": false,
   "tape_cells_log10": 33,
   "checkpoint": "work/ckpt_TM13_D.pkl"
  },
  "TM13_from_C_602": {
   "ticks": 10000000,
   "halted": false,
   "tape_cells_log10": 33,
   "checkpoint": null
  },
  "TM13_from_B_299": {
   "ticks": 7627000,
   "halted": false,
   "tape_cells_log10": 33,
   "checkpoint": "work/ckpt_TM13_B.pkl"
  },
  "TM13_from_A_check": {
   "ticks": 64832,
   "halted": true
  },
  "TM7_from_A_check": {
   "ticks": 65400,
   "halted": true
  }
 },
 "priority_call_answered": "No halt in 16.5M executor ticks. Park the CB1 cluster (412, 602, 299), or fund one 2 h stage for an exact level accelerator of the late PL stack (cryptid stop if the per-level map branches on remainders mod 5)?",
 "parked": "Dennis 2026-10-14: park"
}
observe.json contract (tools/README-card.md):
1 contract warning
  • template file not in the pinned tree: ChaoticBell1Halt.v