Consider a negative unity feedback system with forward path transfer function $G(s)= \dfrac{K}{(s+a)(s-b)(s+c)}$, where $K,a,b,c$ are positive real numbers. For a Nyquist path enclosing the entire imaginary axis and right half of the $s$-plane in the clockwise direction, the Nyquist plot of $(1+G(s))$, encircles the origin of $(1+G(s))$-plane once in the clockwise direction and never passes through this origin for a certain value of $K$. Then, the number of poles of $\dfrac{G(s)}{1+G(s)}$ lying in the open right half of the $s$-plane is_______.
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