1RB0LE_1LC1RA_---1LD_0RB1LF_1RD1LA_0LA0RD

1RB0LE_1LC1RA_---1LD_0RB1LF_1RD1LA_0LA0RD (bbch) is a non-halting BB(6) Turing machine.

Analysis by @racheline on 29 July 2024 (Discord link):

1RB0LE_1LC1RA_---1LD_0RB1LF_1RD1LA_0LA0RD
A(n) = 0^inf <A 0 1^n

rules:
A(6n) -> A(12n+3)
A(6n+1) -> A(12n+6)
A(6n+2) -> halt
A(6n+3) -> A(9n+9)
A(6n+4) -> halt
A(6n+5) -> A(9n+12)
start from A(3)

as we can see, everything that doesn't halt goes to A(6m) or A(6m+3) for some m, so halting is unreachable

the next two (1RB0LE_1LC1RA_---1LD_0RB1LF_1RD1LA_1RD0LA and 1RB0LE_1LC1RA_---1LD_0RB1LF_1RD1LA_0LA0LA) are clearly equivalent to it, so also non-halting