Generalized von Neumann Theorem for Arithmetic Progressions Combinatorics Product Form of the Axiom of Choice Logic Axiom of Choice Implies Dependent Choice Implies Countable Choice Logic Existence of Successor Cardinals Logic Freiman--Ruzsa Theorem for Abelian Groups Combinatorics The Pumping Lemma Discrete Mathematics Mostowski Collapse Lemma Logic Curry-Howard Correspondence for Implicational Intuitionistic Logic Logic Discrete Mathematics Area