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**Peter Krautzberger**Elusive semantics**Joel David Hamkins**When does every definable nonempty set have a definable element?**Dana C. Ernst**My Students’ Favorite Problems from Spring 2017**Joseph Van Name**How cryptocurrencies could incentivize the development of efficient reversible computers and the cryptocurrency market cap reaches 100 billion dollars.**Joel David Hamkins**A model of the generic Vopěnka principle in which the ordinals are not $\Delta_2$-Mahlo**Joel David Hamkins**The universal definition — it can define any mathematical object you like, in the right set-theoretic universe**Joseph Van Name**2D heat maps and 3D topographical surfaces from endomorphic Laver tables**Victoria Gitman**A model of the generic Vopěnka principle in which the ordinals are not $\Delta_2$-Mahlo**Peter Krautzberger**Carnival of Math No. 146**Joel David Hamkins**The universal algorithm: a new simple proof of Woodin’s theorem

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