namespace boost {
  namespace numeric {
    namespace odeint {
      template<typename Stepper, typename System, typename State,
               typename Time, typename Observer, typename StepOverflowChecker>
        Time integrate_n_steps(Stepper stepper, System system,
                               State & start_state, Time start_time, Time dt,
                               size_t num_of_steps, Observer observer,
                               StepOverflowChecker checker);
      // Solves the forwarding problem, can be called with Boost.Range as start_state. 
      template<typename Stepper, typename System, typename State,
               typename Time, typename Observer, typename StepOverflowChecker>
        Time integrate_n_steps(Stepper stepper, System system,
                               const State & start_state, Time start_time,
                               Time dt, size_t num_of_steps,
                               Observer observer,
                               StepOverflowChecker checker);
      template<typename Stepper, typename System, typename State,
               typename Time, typename Observer>
        Time integrate_n_steps(Stepper, System, State &, Time, Time, size_t,
                               Observer);
      // Solves the forwarding problem, can be called with Boost.Range as start_state. 
      template<typename Stepper, typename System, typename State,
               typename Time, typename Observer>
        Time integrate_n_steps(Stepper stepper, System system,
                               const State & start_state, Time start_time,
                               Time dt, size_t num_of_steps,
                               Observer observer);
      // The same function as above, but without observer calls. 
      template<typename Stepper, typename System, typename State,
               typename Time>
        Time integrate_n_steps(Stepper stepper, System system,
                               State & start_state, Time start_time, Time dt,
                               size_t num_of_steps);
      // Solves the forwarding problem, can be called with Boost.Range as start_state. 
      template<typename Stepper, typename System, typename State,
               typename Time>
        Time integrate_n_steps(Stepper stepper, System system,
                               const State & start_state, Time start_time,
                               Time dt, size_t num_of_steps);
    }
  }
}