摘要
The cyclicity of four classes of codimension 3 planar polycycles and ensembles containing a saddle node and two hyperbolic saddles is dealt with. The exact cyclicity or cyclicity bound of them is obtained by finitely smooth normal form theory.
The cyclicity of four classes of codimension 3 plnnar polycycles and ensembles containing a saddle-node and two hyperbdic saddles is dealt with. The exnct cyclicity or cyclicity bound of them is obtained by finitely-smooth normal form theory.