Algorithmische Probleme bei Einrelatorgruppen und ihre Komplexität.
Borel equivalence and isomorphism of coanalytic sets [Book]
Diophantine representation of Mersenne and Fermat primes
Dirichlet theorems and prime number hypotheses of a conditional Goldbach theorem.
Fixpoint alternation : arithmetic, transition systems, and the binary tree
Fixpoint alternation: arithmetic, transition systems, and the binary tree
We provide an elementary proof of the fixpoint alternation hierarchy in arithmetic, which in turn allows us to simplify the proof of the modal mu-calculus alternation hierarchy. We further show that the alternation hierarchy on the binary tree is strict, resolving a problem of Niwiński.
Goldbach conjecture.
O desátém Hilbertově problému
On Markov Properties Of Finitely Presented Groups
On Markov properties of finitely presented groups.
On the Goldbach conjecture and the consistency of general recursive arithemetic.
Proof of the quadratic reciprocity law in primitive recursive arithmetic.
Reduction of an arbitrary diophantine equation to one in 13 unknowns
Relations diophantiennes et la solution négative du 10e problème de Hilbert
Representable P. Martin-Löf tests
Semisemiological structure of the prime numbers and conditional Goldbach theorems.
Some structure theorems for inverse ω-semigroups
String Matching And Algorithmic Problems In Free Groups.
The complexity of uniform distribution
The strength of Turing determinacy within second order arithmetic
We investigate the reverse mathematical strength of Turing determinacy up to Σ₅⁰, which is itself not provable in second order arithmetic.