Logic, applicative programs with recurrence operators, Ramified recurrence, Free algebras, Kalmar-elementary functions, functionals, Complexity classes (hierarchies, relations among complexity classes, etc.), functional programs over free algebras, Complexity of computation (including implicit computational complexity), Logic in computer science, computational complexity, ramified recurrence, higher type recurrence, Theory of programming languages, purely applicative higher-type programs, Functionals in proof theory, Models of computation (Turing machines, etc.), primitive recursion, Higher type functions, equational recurrence, Recursive functions and relations, subrecursive hierarchies, Computational complexity, higher type functions, Cut-elimination and normal-form theorems, Primitive recursion, feasibility