Gentzen's Theorem on the Proof-Theoretic Ordinal of Peano Arithmetic Logic Albert's Theorem Combinatorics Plünnecke Magnification Inequality Combinatorics Algebraic Independence of the Elementary Symmetric Functions Combinatorics Partial Type Characterization of Saturation Logic Parse Trees Characterise the Language Discrete Mathematics Baldwin-Lachlan Dimension Theorem for Uncountable Models Logic Subformula Property for Cut-Free LK and LJ Logic Discrete Mathematics Area Combinatorics Subarea