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How many square roots can a non-identity element in a group have?

Does any set of dominoes tile some common figure?

Is there an elementary proof that distal maps are invertible?

Is every path with this property shorter than another path with the same endpoints?

Is the property of not containing $\mathbb{F}_2$ invariant under quasi-isometry?

Is Thompson's group definably orderable?

Hopping geodesics

Is Thompson's group $T$ co-Hopfian?

Does the Ackermann function count something?

Which convex bodies can be captured in a knot?

Is irreducibility of polynomials $\in \mathbb{Z} [X]$ over $\mathbb{Q}$ an undecidable problem?

Subwords of the infinite Fibonacci word

Sequence of epimorphisms of residually finite groups stabilizes

Cohomology for extension problems in symbolic/topological dynamics?

Diameter of the modified bubble-sort graph

Bounded open sets with same boundaries

2D quadrant sandpile: emergent highway structure

Uses for Sharkovskii's theorem

Construction of minimal zero entropy measure-theoretically strong mixing subshift?

Topological dynamical systems with only zero-entropy factors

Is it true that $(X,T^k)$ minimal for all $k\geq1$ implies $\mathrm{Aut}(X,T) = \mathrm{Aut}(X,T^k)$ for all $k\geq1$?

Is the group ring of an amenable group, viewed as multiplicative monoid, amenable?

Ergodic decomposition of the action of a subgroup

Bernoulli percolation, infinite path from (0,0) in a "cone"

Turing machines with all runs decidable

Minimum real number for subset sum difference

The critical exponent function

Busy beaver sequence for a simple tag-like system

Is Toom's rule robust under local but non-on-site noise?

Is there a description of cellular automata in form of sheaves?