Rewrote function remove_suc, since it failed on some equations produced by recdef.
Rewrote function remove_suc, since it failed on some equations
produced by recdef.

MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle