已知正项等比数列\(\{a_{n}\}\)中，\(a_{4}-a_{2}=6\)，\(a_{5}-a_{1}=15\)，则\(a_{n}=\)______，又数列\(\{b_{n}\}\)满足\(b_{1}=\dfrac{1}{2}\)，\(b_{n+1}=\dfrac{1}{1-b_{n}}\)；若\(S_{n}\)为数列\(\{a_{n}+b_{n}\}\)的前\(n\)项和，那么\(S_{11}=\)______.