Published online by Cambridge University Press: 12 March 2014
It is shown that if κ is an uncountable successor cardinal in L[0#], then there is a normal tree T ϵ L[0#] of height κ such that 0# ∉ L[T], yet T is < κ-distributive in L[0#]. A proper class version of this theorem yields an analogous L[0#]-definable tree such that distinct branches in the presence of 0# collapse the universe. A heretofore unutilized method for constructing in L[0#] generic objects for certain L-definable forcings and “exotic sequences”, combinatorial principles introduced by C. Gray, are used in constructing these trees.