In this paper it is shown that the intuitionistic xed point theory c i (strict) for times iterated xed points of strictly positive operator forms is conservative for negative arithmetic and 0 sentences over the theory ACA i for times iterated arithmetic comprehension without set parameters. This generalizes results previously due to Buchholz [5] and Arai [2].
['Christian Rüede', 'Thomas Strahm']
Intuitionistic Fixed Point Theories for Strictly Positive Operators