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Conjecture Distributivity of the lattice
of funcoids (for arbitrary sets
and
) is not provable in ZF (without axiom of choice).
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A similar conjecture:
Conjecture
for arbitrary filters
and
on a powerset cannot be proved in ZF (without axiom of choice).
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See this blog post for a rationale of this conjecture.
See here for used notation.
The first conjecture is shown false (that is a proof without AC exists) by Todd Trimble.
* indicates original appearance(s) of problem.