Time-efficient implementation of the safe PI function–based algorithms for Tarski* and Tarski
Ascertain whether the O(log n)-query algorithm for Tarski*(n,3), and the induced O(log^2 n)-query algorithm for Tarski(n,4), can be implemented with efficient time complexity rather than relying on the currently non–time-efficient safe partial-information framework and brute-force steps.
References
It is an important open problem whether the algorithm can be implemented efficiently in terms of time complexity.
— The Mystery Deepens: On the Query Complexity of Tarski Fixed Points
(2604.00268 - Chen et al., 31 Mar 2026) in Section 7 (Conclusion and Discussion)