BB(6) hunt

1RB1LC_1RC---_1LD1LC_1RE0LC_1RF0RE_1RA0RD

#6Cryptid candidateStructural counter + chaotic edgebbchallenge ↗Explorer

Where it stands

Cryptid candidate, parked at the deeper analysis

Stopped by Dennis 2026-10-10: stays cryptid candidate, proof work parked with twin #27 (1RB0RA_1RC0RF_1RD1LE_1RE---_1LF1LE_1RA0LE). Halting reduces exactly to a validated 5-stage chain on the cluster 11.01.00, with arrival phases x,E,x,x,E (60/60 random instances halt).

Read the full status

Seeds of this chain keep forming in the disordered mixed zone: 11 by 2.45e10 steps, about 0.7 per doubling. Their later stages depend only on left-context mod-4 phases, and those match the generic coin rates (about 50/35/13/50%); nothing visible forces them. The step-12,975,111 near miss is seed #3, which got through x,E,x. Under the coin model each seed halts with probability about 1%: probabilistic, cryptid-like. Priority call for Dennis: stop, or continue by decoding the mixed zone (would need a rule forcing the stage phases).

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

Defect groups drift left at 1, 3/4, 1/2, 3/8.. cells/bounce: exact 16-bounce counter on left, chaotic edge on right

Status
Cryptid candidatedeepen2 · updated 2026-10-10Parked · Stopped by Dennis 2026-10-10: stays cryptid candidate, proof work parked with twin #27 (1RB0RA_1RC0RF_1RD1LE_1RE---_1LF1LE_1RA0LE). The 2 open questions are optional.
idle since Oct 10 12:49 · status.json 2026-10-10
Class
Structural counter + chaotic edgeours: Structural counter + chaotic edge (sheet) · ours adds: drifting defect groups (hierarchical counter) fed by a chaotic right edge · med confidence
On the list
line 324 of BB6_holdouts_663.txt · historical 740 line 358
#6eqv ×1table ×2sim 1e15UBRRBA
Your calls on file 2
parked
Stopped by Dennis 2026-10-10: stays cryptid candidate, proof work parked with twin #27 (1RB0RA_1RC0RF_1RD1LE_1RE---_1LF1LE_1RA0LE).
decision.json · answered 2026-10-10: stop
Stop work on #6 and its twin #27: keep #6 flagged CRYPTID_CANDIDATE and park proof work, rather than spend a stage decoding the mixed zone? Decisions →

Mechanism

How it works: 3 notes
  • Tape: (01)^n runs split by single defects (11, 00, 1111); the head zig-zags between them; the wall grows 2 cells/bounce.
  • Defect groups drift left from the right edge at exact speeds 1, 3/4, 1/2, 3/8...; left block repeats every 16 bounces.
  • The right edge is chaotic (hi ~ 20·sqrt(L)). Halting needs E to sweep an odd (10) run ending in 00: unseen to 1e11.

Figures for Checkpoint A

Fig 1 · Left records, every 4th cellQ1

2 rows per wall bounce, every 4th cell; each white/black edge is a defect. Follow the edges downward.

Left records, every 4th cell
bbchallenge-defaultStart blankRows the start, then one per new leftmost cell = 2 per wall bounceWindow cells -4,999..1,476, 1 px = 4 cellsColors 1 0 or never visited (top-left) line: head at the wall
Rows: (5,000 rows, steps 0..25,015,029; stopped at the 5,000-row cap); not evenly spaced in time · Window: only the first cell of each 4 is drawn · Colors: Only every 4th cell is drawn, so a 0101... run shows as solid white or solid black (its phase), and every white/black edge inside the tape is a defect (00, 11 or 1111)
Fig 2 · Right edge pinned, defects onlyQ2

Right edge pinned, defects only (black). Compare the dense band at the right edge with the slanted lines leaving it.

Right edge pinned, defects only
customStart blankRows the start, then one per new rightmost cellWindow cells -1,599..0, 1 px = 2 cellsColors at least one defect (00 or 11) among the pixel's 2 cells clean 0101... run not yet visited
Rows: (2,819 rows, steps 0..969,848,428; no new right cell from then to 1e9); not evenly spaced in time · Window: counted from the right edge (each row's rightmost visited cell is 0, pinned to the last column; it is absolute cell 2,818 in the last row) · Colors: head not drawn; Each slanted line = a defect drifting left, away from the edge; the dense band at the right = the chaotic edge zone
More figures (3)Fig 3–5: Defects to 1e9, left wall pinned · Blaze, 100M steps · bbchallenge default view, first 10,000 steps
Fig 3 · Defects to 1e9, left wall pinned

Defect groups drift away from the wall; lines curve only because rows are equal in steps, not bounces.

Defects to 1e9, left wall pinned
customStart blankRows every 500,000 stepsWindow cells 0..36,470, 1 px = 8 cellsColors at least one defect (two equal neighbours, 00 or 11) among the pixel's 8 cells clean 0101... run not yet visited
Rows: steps 0, 500,000, ..., 1,000,000,000 (2,001 rows), so consecutive rows are 500,000 steps apart · Window: counted from the wall (each row's leftmost visited cell is 0, pinned to column 0; it is absolute cell -33,652 in the last row) · Colors: head not drawn; Isolated dots = the head's own working cells at that moment; Lines curve because rows are evenly spaced in steps, not in bounces
Fig 4 · Blaze, 100M steps

The wall grows like sqrt(t); the right edge stays ragged and almost still.

Blaze, 100M steps
bbchallenge-blazeStart blankRows time blocks of 131,072 stepsWindow cells -10,360..1,751, 1 px = ~15 cellsColors 0 1
Rows: averaged (763 blocks, steps 0..100,000,000), stretched to 500 px: 1 px ~ 200,000 steps · Window: Blaze averages 8 cells per column; its 1,514 columns are stretched to 800 px · Colors: in-between shades = both mixed inside the pixel's block (averaged); no head
Fig 5 · bbchallenge default view, first 10,000 stepsviewer ↗

The site's view of the first 10,000 steps: zig-zag bounces between defects.

bbchallenge default view, first 10,000 steps
bbchallenge-defaultStart blankRows every step: steps 0..9,999 squeezed into 500 px rows as on bbchallenge.orgWindow cells -200..199, 1 px = 1 cellColors 1 0 or never visited head after a right/left move
Rows: each px row blends steps 20y+9 and 20y+10, so 1 px row = 20 steps · Colors: red/green: pale colours = blended by the squeeze
Rules (8/8 validated)exact tape rewrites the proof will formalize, each re-checked by simulation
rulefrom ⟶ tocasesstepschecked
G16 left block (16 bounces)
0∞ <D 11 (01)14 (10)a 14 (01)3 12 (10)8 (01)b (10)12 1 (10)c 13 (10)6 (01)18 0 (01)2 r
⟶ 0∞ <D 11 (01)14 (10)a+8 14 (01)3 12 (10)8 (01)b+2 (10)12 1 (10)c+2 13 (10)6 (01)18 0 (01)2 r'
a odd >= 1, b even >= 4, c even >= 2, independent; r = real right part (4 tapes, 1e7..1e9). Other parity classes: 0/12 pass (wrong guess killed). [Notation fixed at assembly: was '<D 011 ...', which puts an extra 0 left of the 11; re-checked 30/30 in sim notation.]—✓32/32
orbit lock
c0 (blank tape)
⟶ G16 skeleton with (a,b,c,d) = (8n+61, 2n, 2n-2, n), L = 32n+26, at every 16th wall visit
observed on the orbit (25 snapshots, n = 25..1051), not a random-parameter test—✓25/25
H halt trigger
E> (10)2n+1 001
⟶ halt (B reads 1)
sibling E> 10^(2n) 001 -> 01^(2n) 1 1 <C 1 in 4n+3 (safe turn), 40/404n+5 (busycoq halts_in 4n+4)✓40/40
left sweep
(10)n <C
⟶ <C (01)n
—2n✓40/40
right sweep, even
E> (01)2n
⟶ (10)2n E>
also E> 10^(2n) -> 01^(2n) E> in 4n4n✓80/80
right sweep, odd
E> (01)2n+1
⟶ (10)2n+1 D>
also E> 10^(2n+1) -> 01^(2n+1) F> in 4n+2 (F then reads the next cell: 0 0 1 there = halt)4n+2✓80/80
wall bounce
0∞ <C
⟶ 0∞ 1 0 E>
—3✓40/40
edge extension
E> 0∞
⟶ 1 <C 1101 0∞
the only place B is entered in 1e9 steps (512 times); B always reads 0 there8✓40/40
Compressed historythe tape as 0∞ <D 11 (01)14 (10)a 14 (01)3 12 (10)8 (01)b (10)12 1 (10)c 13 (10)6 (01)18 0 (01)d 13 (01)6 r at 25 moments: where the rules are read off
0∞ <D 11 (01)14 (10)a 14 (01)3 12 (10)8 (01)b (10)12 1 (10)c 13 (10)6 (01)18 0 (01)d 13 (01)6 r
stepabcdL (=-lo)hidefects
1,074,148261504825826893102
1,363,63829358562995498198
1,824,2223417068351,146992111
2,547,4764058684431,4021,036117
3,379,994469102100511,6581,058115
4,342,350533118116591,9141,124117
5,697,176613138136692,2341,157106
7,590,424709162160812,6181,223100
10,120,334821190188953,0661,300123
13,434,2509492222201113,5781,344113
18,237,1761,1092622601314,2181,388119
23,714,0881,2693023001514,8581,465152
31,886,5441,4773543521775,6901,520139
42,795,1461,7174144122076,6501,553156
56,264,1181,9734784762397,6741,641150
75,566,1082,2935585562798,9541,718171
100,001,5382,64564664432310,3621,751176
133,437,9323,06175074837512,0261,850171
177,848,6423,54187086843513,9461,883182
237,710,7444,1011,0101,00850516,1861,960171
316,436,3424,7411,1701,16858518,7461,960183
423,685,3225,4931,3581,35667921,7542,158213
563,100,5526,3411,5701,56878525,1462,356235
751,446,2027,3331,8181,81690929,1142,587262
1,000,348,9988,4692,1022,1001,05133,6582,818275
alast 8,469
8,4692611.1e61e9step 1074148: a = 261step 1363638: a = 293step 1824222: a = 341step 2547476: a = 405step 3379994: a = 469step 4342350: a = 533step 5697176: a = 613step 7590424: a = 709step 10120334: a = 821step 13434250: a = 949step 18237176: a = 1109step 23714088: a = 1269step 31886544: a = 1477step 42795146: a = 1717step 56264118: a = 1973step 75566108: a = 2293step 100001538: a = 2645step 133437932: a = 3061step 177848642: a = 3541step 237710744: a = 4101step 316436342: a = 4741step 423685322: a = 5493step 563100552: a = 6341step 751446202: a = 7333step 1000348998: a = 8469
blast 2,102
2,102501.1e61e9step 1074148: b = 50step 1363638: b = 58step 1824222: b = 70step 2547476: b = 86step 3379994: b = 102step 4342350: b = 118step 5697176: b = 138step 7590424: b = 162step 10120334: b = 190step 13434250: b = 222step 18237176: b = 262step 23714088: b = 302step 31886544: b = 354step 42795146: b = 414step 56264118: b = 478step 75566108: b = 558step 100001538: b = 646step 133437932: b = 750step 177848642: b = 870step 237710744: b = 1010step 316436342: b = 1170step 423685322: b = 1358step 563100552: b = 1570step 751446202: b = 1818step 1000348998: b = 2102
clast 2,100
2,100481.1e61e9step 1074148: c = 48step 1363638: c = 56step 1824222: c = 68step 2547476: c = 84step 3379994: c = 100step 4342350: c = 116step 5697176: c = 136step 7590424: c = 160step 10120334: c = 188step 13434250: c = 220step 18237176: c = 260step 23714088: c = 300step 31886544: c = 352step 42795146: c = 412step 56264118: c = 476step 75566108: c = 556step 100001538: c = 644step 133437932: c = 748step 177848642: c = 868step 237710744: c = 1008step 316436342: c = 1168step 423685322: c = 1356step 563100552: c = 1568step 751446202: c = 1816step 1000348998: c = 2100
dlast 1,051
1,051251.1e61e9step 1074148: d = 25step 1363638: d = 29step 1824222: d = 35step 2547476: d = 43step 3379994: d = 51step 4342350: d = 59step 5697176: d = 69step 7590424: d = 81step 10120334: d = 95step 13434250: d = 111step 18237176: d = 131step 23714088: d = 151step 31886544: d = 177step 42795146: d = 207step 56264118: d = 239step 75566108: d = 279step 100001538: d = 323step 133437932: d = 375step 177848642: d = 435step 237710744: d = 505step 316436342: d = 585step 423685322: d = 679step 563100552: d = 785step 751446202: d = 909step 1000348998: d = 1051
L (=-lo)last 33,658
33,6588261.1e61e9step 1074148: L (=-lo) = 826step 1363638: L (=-lo) = 954step 1824222: L (=-lo) = 1146step 2547476: L (=-lo) = 1402step 3379994: L (=-lo) = 1658step 4342350: L (=-lo) = 1914step 5697176: L (=-lo) = 2234step 7590424: L (=-lo) = 2618step 10120334: L (=-lo) = 3066step 13434250: L (=-lo) = 3578step 18237176: L (=-lo) = 4218step 23714088: L (=-lo) = 4858step 31886544: L (=-lo) = 5690step 42795146: L (=-lo) = 6650step 56264118: L (=-lo) = 7674step 75566108: L (=-lo) = 8954step 100001538: L (=-lo) = 10362step 133437932: L (=-lo) = 12026step 177848642: L (=-lo) = 13946step 237710744: L (=-lo) = 16186step 316436342: L (=-lo) = 18746step 423685322: L (=-lo) = 21754step 563100552: L (=-lo) = 25146step 751446202: L (=-lo) = 29114step 1000348998: L (=-lo) = 33658
hilast 2,818
2,8188931.1e61e9step 1074148: hi = 893step 1363638: hi = 981step 1824222: hi = 992step 2547476: hi = 1036step 3379994: hi = 1058step 4342350: hi = 1124step 5697176: hi = 1157step 7590424: hi = 1223step 10120334: hi = 1300step 13434250: hi = 1344step 18237176: hi = 1388step 23714088: hi = 1465step 31886544: hi = 1520step 42795146: hi = 1553step 56264118: hi = 1641step 75566108: hi = 1718step 100001538: hi = 1751step 133437932: hi = 1850step 177848642: hi = 1883step 237710744: hi = 1960step 316436342: hi = 1960step 423685322: hi = 2158step 563100552: hi = 2356step 751446202: hi = 2587step 1000348998: hi = 2818
defectslast 275
275981.1e61e9step 1074148: defects = 102step 1363638: defects = 98step 1824222: defects = 111step 2547476: defects = 117step 3379994: defects = 115step 4342350: defects = 117step 5697176: defects = 106step 7590424: defects = 100step 10120334: defects = 123step 13434250: defects = 113step 18237176: defects = 119step 23714088: defects = 152step 31886544: defects = 139step 42795146: defects = 156step 56264118: defects = 150step 75566108: defects = 171step 100001538: defects = 176step 133437932: defects = 171step 177848642: defects = 182step 237710744: defects = 171step 316436342: defects = 183step 423685322: defects = 213step 563100552: defects = 235step 751446202: defects = 262step 1000348998: defects = 275
Template comparisonBLv3.v TM1: partly applies · the nearest solved proof, what carries over, and the transitions that differ
01
A1RB1LC
B1RC---
C1LD1LC
D1RE0LC
E1RF0RE
F1RA0RD

differs from the template

file
BLv3.v:7
module
TM1 (TM2 shares it)
machine
1RB0RA_1LC0RD_0LD0LB_1RA1LE_0LC1LF_0LA--- (11 transitions apart)
diff
8 of 11 transitions differ under best relabeling (A0 A1 B0 C1 D0 E0 E1 F1); BLv3 TM2 8, BLv2 TM1-3 8-9, Bouncer_v4 9
note
Method carries: columns (01)^n+defect, head passes as a signal stream, per-column transducer + quadRect closure. Lemmas don't: we add 1111 columns, our edge grows, and BLv3's own cut tape halts on our machine at sim step 20,175.
Proof strategy & riskshow the formal proof will go · 3 risks to watch

BLv3-style. 1) es/ind for sweep/wall/edge rules; 2) the 16-bounce left-block rule with a odd, b,c even (multistep_nonhalt + progress_nonhalt_cond on n); 3) the hard part: a closed (regular) set for the edge region that excludes 'E> 10^odd 001' (LongN/InfiniteRect quadRect, or a CTL-style language search first).

  • ▲Edge is chaotic and growing (hi ~ 20*sqrt(L), 56 groups at 1e9): a finite closed set may not exist -> STUCK at step 3.
  • ▲Halting is a parity event (odd (10) run before a 00 defect); a late halt like BLv2's 3 kills is possible. None to 1e11.
  • ▲On mxdys's UBRRBA_TODO list (Dennis: fair game); twin #27 is this exact table started in state E, so one proof should cover both.
Stats & provenance1011 steps simulated · 352,865 cells · the status in full · files
simulated
1011 steps
tape
352,865 cells · 177,158 nonzeros
growth
wall L ~ 1.08*sqrt(t) (2 cells/bounce); right edge hi ~ 20*sqrt(L) ~ t^0.25; defects 99 -> 275 (1e6 -> 1e9)
status now
Stopped by Dennis 2026-10-10: stays cryptid candidate, proof work parked with twin #27 (1RB0RA_1RC0RF_1RD1LE_1RE---_1LF1LE_1RA0LE). Halting reduces exactly to a validated 5-stage chain on the cluster 11.01.00, with arrival phases x,E,x,x,E (60/60 random instances halt). Seeds of this chain keep forming in the disordered mixed zone: 11 by 2.45e10 steps, about 0.7 per doubling. Their later stages depend only on left-context mod-4 phases, and those match the generic coin rates (about 50/35/13/50%); nothing visible forces them. The step-12,975,111 near miss is seed #3, which got through x,E,x. Under the coin model each seed halts with probability about 1%: probabilistic, cryptid-like. Priority call for Dennis: stop, or continue by decoding the mixed zone (would need a rule forcing the stage phases). (status.json, 2026-10-10)
observer's note
Left counter found and validated; edge chaotic but no Collatz-like arithmetic (gaps grow linearly). Needs Dennis's call on the edge approach.
files
observe.json · notes.md · status.json

Proof & checks

○ Checkpoint B: no note from Dennis found

  • notes.md L54: - Checkpoint questions are now yes/no questions about the figures. Moved off the card (strategy calls, not figure reading; settle them in proof.md / Checkpoint B):

Files

machines/<tm>/: 13 entries · raw notes, status, scripts, images

namesizechanged
notes.md ↓18 KB2026-10-10 12:49
status.json ↓1.1 KB2026-10-10 12:49
observe.json ↓13 KB2026-10-10 04:41
deepen.json ↓6.3 KB2026-10-10 07:09
decision.json ↓4.0 KB2026-10-10 12:49
data/3 items2026-10-10 07:09
img/8 items2026-10-10 01:55
scripts/30 items2026-10-10 07:09
qsim.jsonl ↓13 KB2026-10-10 00:08
qsim_n1.jsonl ↓654 B2026-10-10 00:11
qsim_n2_summary.jsonl ↓10 KB2026-10-10 00:34
sim_records_1e11.jsonl.gz ↓3.6 MB2026-10-10 00:24
sim_records_1e9.jsonl.gz ↓374 KB2026-10-10 00:07
status.json in full
{
 "tm": "1RB1LC_1RC---_1LD1LC_1RE0LC_1RF0RE_1RA0RD",
 "status": "CRYPTID_CANDIDATE",
 "stage": "deepen2",
 "updated": "2026-10-10",
 "reason": "Stopped by Dennis 2026-10-10: stays cryptid candidate, proof work parked with twin #27 (1RB0RA_1RC0RF_1RD1LE_1RE---_1LF1LE_1RA0LE). Halting reduces exactly to a validated 5-stage chain on the cluster 11.01.00, with arrival phases x,E,x,x,E (60/60 random instances halt). Seeds of this chain keep forming in the disordered mixed zone: 11 by 2.45e10 steps, about 0.7 per doubling. Their later stages depend only on left-context mod-4 phases, and those match the generic coin rates (about 50/35/13/50%); nothing visible forces them. The step-12,975,111 near miss is seed #3, which got through x,E,x. Under the coin model each seed halts with probability about 1%: probabilistic, cryptid-like. Priority call for Dennis: stop, or continue by decoding the mixed zone (would need a rule forcing the stage phases).",
 "parked": "Stopped by Dennis 2026-10-10: stays cryptid candidate, proof work parked with twin #27 (1RB0RA_1RC0RF_1RD1LE_1RE---_1LF1LE_1RA0LE)."
}