BB(6) hunt
Machines / W7-6

1RB0LA_1RC---_0LD1RD_0RA0RE_0RF1RC_1LF0LA

W7-6Cryptid candidateTranslated Counterbbchallenge ↗Explorer

Where it stands

Cryptid candidate, parked at the observation

Stage 1 (W7-6) stopped by its stop rule. The counting phase is exact: at every C right record the word is a base-4 counter on pairs of 1-runs (23=0, 22=1, 33=2, 32=3, top digit 3) and each record adds 1 (10,416/10,416 random transitions, w = 2..40); it cannot halt while counting.

Read the full status

Halting is possible only at phase events: overflow -> A erases the trail -> nested rebuild -> the new counter collides with markers / the old remnant. Synthetic scans show a collision halts only for an exact (value, gap) pair (w=3: V=49, gap 28 halts at 6,290 steps). The real orbit survived every event to 2.1e7; the current 23-pair counter (V = 61,170,343,443,693 at step 100,000,903, irregular high digits) overflows after ~9.2e12 increments, about 4.6e15 steps, trail ~1.8e13. Whether that transition halts is an exact big-number coincidence question: cryptid-like lottery, not settled. No nonhalting work (taken class, M-Abozaid SOTCv2.v).

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

Exact base-4 counter while counting; halts only at overflow/collision events hinging on exact coincidences.

Status
Cryptid candidatewave7-stage1 · updated 2026-10-14Parked · Stage 1 (W7-6) stopped by its stop rule. The 2 open questions are optional.
idle since Oct 16 10:32 (2 h ago) · status.json 2026-10-14
Class
Translated Counterours: sheet Translated Counter ≠ ours Translated base-4 counter with overflow, trail erase and nested rebuild (phase cycle) · med confidence
On the list
line 29 of BB6_holdouts_663.txt · historical 740 line 33 · observe.json rank #33
eqv ×1sim 1e13
Your calls on file 1
decision.json · answered 2026-10-16: park
Park line 33 as a cryptid-like translated counter, or fund one 2 h stage to build the exact phase model and decide the transition at ~4.6e15 steps? Decisions →

Mechanism

How it works: 7 notes
  • Counting phase: a ~4w+3-cell counter moves right over blank tape and leaves a trail 1^N behind; each tick the head sweeps the whole counter left and back.
  • At every C right record the word is 0^inf L 1^N 0^2 s_1 0 s_2 0 ... s_2w 0 1 C> 0^inf with s_i in {1^2, 1^3}; pairs are base-4 digits MSB first: 23=0, 22=1, 33=2, 32=3; '4 3' = digit 0 with a pending carry.
  • Rule R1 (exact, 10,416/10,416 random record transitions, w = 2..40): each C right record shows value V+1. The top digit is always 3, so a w-pair counter runs at most 4^(w-1) increments.
  • Overflow (all digits 3 + carry): A sweeps left erasing the trail (A1 = 0LA); separators 0 1^2 0 become single-1 markers; a small counter is rebuilt at the left end and counts through the gap.
  • Collision: when the counter front reaches a marker or the old counter's remnant, it either absorbs it (counter grows) or halts. Synthetic scans: the outcome depends on the exact (value, gap) pair, e.g. w=3, V=49, gap 28 halts at step 6,290.
  • History: phase 1 (8 pairs) overflowed at 3.73e6; nested rebuilds 3.7e6-2.1e7 (gaps 0^(2*4^k-2)); the current phase is a 23-pair counter (V = 61,170,343,443,693 at step 100,000,903) that overflows after ~9.2e12 more increments, ~4.6e15 steps, trail ~1.8e13.
  • Family: lines 472, 569, 690 are distinct tables (not starts of 33's table) with the same architecture by end tapes (1^5408013, 1^4591407, 1^10536 0 1^2 0 1^5410013 at 1e9); qsim 0 rules on all four.

Figures for Checkpoint A

Fig 1 · Phases to 2.2e7: count, erase, rebuildQ1

White wedges are counting phases; the near-flat lines are A erasing the trail after an overflow.

Phases to 2.2e7: count, erase, rebuild
bbchallenge-defaultStart blankRows every 20,000 steps (1101 rows, to step 2.2e7)Window cells -81..89,280, 1 px = 128 cellsColors 1 0
Colors: black: each pixel samples one of 128 cells
Fig 2 · Two counter ticks, w = 4 pairs

Each tick the head crosses the whole counter; compare the digit blocks before and after each sweep.

Two counter ticks, w = 4 pairs
bbchallenge-defaultStart constructed tape (below)Rows every step (701 rows)Window cells -84..15, 1 px = 1 cellColors 1 0
Start: 0∞ 13 0 12 0 15 0 140 02 13 0 12 0 12 0 13 0 13 0 12 0 13 0 12 0 1 C> 0∞ · Window: PNG upscaled 2x · Colors: coloured pixel = head (bbchallenge colours)
Fig 3 · A collision that haltsQ2

The counter absorbs the marker, overflows, rebuilds and halts: halting needs this exact value/gap coincidence.

A collision that halts
bbchallenge-defaultStart constructed tape (below)Rows every 8 steps; last row = halt at step 6290Window cells -90..47, 1 px = 1 cellColors 1 0
Start: 0∞ 13 0 12 0 15 0 130 02 13 0 12 0 12 0 13 0 12 0 12 0 1 C> 028 1 0∞ · Colors: coloured pixel = head (bbchallenge colours)
More figures (1)Fig 4: bbchallenge view, 10,000 steps
Fig 4 · bbchallenge view, 10,000 stepsviewer ↗

The site's own picture, for orientation.

bbchallenge view, 10,000 steps
bbchallenge-defaultStart blankRows every step, 10,000 steps squeezed into 500 rowsWindow cells -200..199, 1 px = 1 cellColors 1 0
Rows: site canvas · Window: site canvas 400x500 · Colors: coloured pixel = head (bbchallenge colours)
Rules (4/4 validated)exact tape rewrites the proof will formalize, each re-checked by simulation
rulefrom ⟶ tocasesstepschecked
R1 record increment
0∞ L 1N 02 enc_w(V) 1 C> 0∞
⟶ next C right record: enc_w(V+1) (carry shown as '4 3')
V < 4^w - 1; top digit 3~20 (low pair) or one full sweep, ~502 per increment at w=23✓10416/10416
R2 digit code
pair (s1,s2) of 1-runs
⟶ 23->0, 22->1, 33->2, 32->3
w = 2..40—✓10416/10416
R3 trail growth
N
⟶ N + ~2 per increment (79,689 over 39,847 increments)
w = 23, measured, not exact—✓1/1
R4 collision outcome
enc_w(V) 1 C> 0g 1 0∞
⟶ absorb (counter grows) or HALT, depending on exact (V, g)
w=3: 3 halting cells of 8 x 48 (one orbit); w=2: V=15 halts for most g—✓432/432
Compressed historythe tape as 0∞ 13 0 12 0 15 0 11322 0 12 0 1N 02 enc23(V) 1 C> 0∞ at 2 moments: where the rules are read off
0∞ 13 0 12 0 15 0 11322 0 12 0 1N 02 enc23(V) 1 C> 0∞
stepNV
100,000,903399,7826.11·1013
119,999,033479,4716.11·1013
Nlast 479,471
4.8e54e51e81.2e8step 100000903: N = 399782step 119999033: N = 479471
Vlast 6.11·1013
6.1e136.1e131e81.2e8step 100000903: V = 61170343443693step 119999033: V = 61170343483540
Template comparisonSOTCv2.v TM1: partly applies · the nearest solved proof, what carries over, and the transitions that differ
01
A1RB0LA
B1RC---
C0LD1RD
D0RA0RE
E0RF1RC
F1LF0LA
file
SOTCv2.v:8
module
TM1
machine
1RB---_0RC1LF_1LC1LD_1RE0RA_0RD1RF_0LD0LF (11 transitions apart)
diff
different table (nearest SOTC/BTC proof >= 5 transitions away)
note
M-Abozaid's token/sweep lemmas fit the counting phase (R1); nothing upstream covers overflow -> erase -> nested rebuild -> collision, where this machine can halt.
Proof strategy & riskshow the formal proof will go · 3 risks to watch

No nonhalting proof attempted (taken class; needs a new decision). HALT route only: an exact phase-level model (R1 closed form + run-length transitions) to decide the transition after the 23-pair counter overflows (~4.6e15 steps).

  • ▲Collision outcomes hinge on exact coincidences of large irregular numbers (the 23-pair start value has irregular digits): cryptid-like lottery.
  • ▲A HALT at ~4.6e15+ needs a checked runner with a formal increment lemma (W5-5-style base-4 digit lemmas).
  • ▲Translated Counter is M-Abozaid's class (SOTCv2.v); nonhalting work needs a separate call.
Stats & provenance109 steps simulated · 3,954,386 cells · the status in full · files
simulated
109 steps
tape
3,954,386 cells · 3,954,346 nonzeros
growth
trail ~2 cells per increment, ~4.0e5 cells per 1e8 steps (linear within a phase)
status now
Stage 1 (W7-6) stopped by its stop rule. The counting phase is exact: at every C right record the word is a base-4 counter on pairs of 1-runs (23=0, 22=1, 33=2, 32=3, top digit 3) and each record adds 1 (10,416/10,416 random transitions, w = 2..40); it cannot halt while counting. Halting is possible only at phase events: overflow -> A erases the trail -> nested rebuild -> the new counter collides with markers / the old remnant. Synthetic scans show a collision halts only for an exact (value, gap) pair (w=3: V=49, gap 28 halts at 6,290 steps). The real orbit survived every event to 2.1e7; the current 23-pair counter (V = 61,170,343,443,693 at step 100,000,903, irregular high digits) overflows after ~9.2e12 increments, about 4.6e15 steps, trail ~1.8e13. Whether that transition halts is an exact big-number coincidence question: cryptid-like lottery, not settled. No nonhalting work (taken class, M-Abozaid SOTCv2.v). (status.json, 2026-10-14)
observer's note
Stage 1 stop rule: counting is exact (R1), but halting happens only at overflow/collision events whose outcome depends on exact coincidences of large irregular numbers.
files
observe.json · notes.md · status.json

Proof & checks

No proof work yet.

Files

machines/<tm>/: 7 entries · raw notes, status, scripts, images

namesizechanged
notes.md ↓6.3 KB2026-10-14 22:51
status.json ↓3.2 KB2026-10-14 22:50
observe.json ↓7.7 KB2026-10-14 22:50
decision.json ↓2.1 KB2026-10-16 10:32
img/7 items2026-10-14 22:50
scripts/9 items2026-10-14 22:47
work/12 items2026-10-14 22:47
status.json in full
{
 "tm": "1RB0LA_1RC---_0LD1RD_0RA0RE_0RF1RC_1LF0LA",
 "label": "W7-6",
 "status": "CRYPTID_CANDIDATE",
 "stage": "wave7-stage1",
 "updated": "2026-10-14",
 "confidence": "med",
 "reason": "Stage 1 (W7-6) stopped by its stop rule. The counting phase is exact: at every C right record the word is a base-4 counter on pairs of 1-runs (23=0, 22=1, 33=2, 32=3, top digit 3) and each record adds 1 (10,416/10,416 random transitions, w = 2..40); it cannot halt while counting. Halting is possible only at phase events: overflow -> A erases the trail -> nested rebuild -> the new counter collides with markers / the old remnant. Synthetic scans show a collision halts only for an exact (value, gap) pair (w=3: V=49, gap 28 halts at 6,290 steps). The real orbit survived every event to 2.1e7; the current 23-pair counter (V = 61,170,343,443,693 at step 100,000,903, irregular high digits) overflows after ~9.2e12 increments, about 4.6e15 steps, trail ~1.8e13. Whether that transition halts is an exact big-number coincidence question: cryptid-like lottery, not settled. No nonhalting work (taken class, M-Abozaid SOTCv2.v).",
 "siblings": [
  {
   "line": 472,
   "tm": "1RB0LA_1RC---_0LD1RD_1RA0RE_0RF1RC_1LF0LA",
   "note": "distinct table (D0 1RA vs 0RA); same architecture by end tape (1^5408013 + ~30-cell counter at 1e9); qsim 0 rules; not modelled"
  },
  {
   "line": 569,
   "tm": "1RB0RD_1RC---_0LA1RA_0RE1RC_1LE0LF_0RC0LF",
   "note": "distinct table; same architecture by end tape (1^4591407 at 1e9); qsim 0 rules; not modelled"
  },
  {
   "line": 690,
   "tm": "1RB0LA_1RC---_0LD1RD_0RB0RE_0RF0LD_1LF0LA",
   "note": "distinct table (D0 0RB, E1 0LD); end tape 1^10536 0 1^2 0 1^5410013 at 1e9; qsim 0 rules; not modelled"
  }
 ],
 "family_note": "The four W7-6 lines are four different tables (canon over all starts, renaming + mirror), not starts of one table; no start-parametric argument applies. Line 33's table has no other start on the 740 list.",
 "template": "SOTCv2.v TM1 (M-Abozaid): applies partly (sweep/token lemmas fit the counting phase); nothing upstream covers overflow -> erase -> nested rebuild -> collision.",
 "checks": {
  "byte_exact_740": "line 33",
  "claims": "none before ours (claims.tsv); sheet: 'Has to halt in the counting phase'; no proof file names any of the 4 lines",
  "ledger": "query 33: parked 10-13 (halting-hunt, retry_if exact model with a margin); qsim/margin scouts negative",
  "qsim": "0 rules on 33/472/569/690 at 200,000 loops (work/qsim_*.jsonl)",
  "sim": "no halt to 1e9 on all four lines (work/sim1e9_*.jsonl)",
  "increment_rule": "scripts/validate_increment.py: 10,416/10,416 record transitions",
  "collision_scan": "scripts/collide_scan.py, scripts/overflow_scan.py, scripts/halt_orbit.py"
 },
 "next_goal": "If funded (2 h): exact phase-level simulator = R1 closed form (exact trail growth and step cost per increment, fitted then validated on random words) + run-length simulation of overflow/erase/nested rebuild/collision, validated against direct simulation to 2.2e7 (3 phase events); then run it through the overflow of the 23-pair counter (~4.6e15 steps) and report HALT (with step count, the C2-552/W5-5 checked-runner route) or the next phase's parameters."
}
observe.json contract (tools/README-card.md):
1 contract warning
  • mechanism: 7 bullets (max 3; the card folds them under the summary)