Asymptotic density of 1s in the Oldenburger–Kolakoski sequence
Determine whether the number of 1s in the length-n prefix of the Oldenburger–Kolakoski sequence is n/2 + o(n) as n tends to infinity.
References
It seems reasonable to conjecture that this number is $n/2 + o(n)$, but this is not currently known.
— Cloitre's Self-Generating Sequence
(2501.00784 - Shallit, 1 Jan 2025) in Section 1, Introduction