Problem:
 a() -> a()
 a() -> b()
 a() -> g(a())
 b() -> g(g(b()))

Proof:
 Uncurry Processor:
  a() -> a()
  a() -> b()
  a() -> f3(g(),a())
  b() -> f3(g(),f3(g(),b()))
  Ground Confluence Processor:
   UNC by decision procedure.