2 papers
math.LO2014
An order-theoretic characterization of the Howard-Bachmann-hierarchy
Jeroen Van der Meeren, Michael Rathjen, Andreas Weiermann
In this article we provide an intrinsic characterization of the famous Howard-Bachmann ordinal in terms of a natural well-partial-ordering by showing that this ordinal can be reali…
math.LO2012
A Simplified Characterisation of Provably Computable Functions of the System ID_1 of Inductive Definitions
Naohi Eguchi, Andreas Weiermann
We present a simplified and streamlined characterisation of provably total computable functions of the theory ID_1 of non-iterated inductive definitions. The idea of the simplifica…