5.
已知等比数列\(\{a_{n}\}\)的首项是\(1\),公比为\(3\),等差数列\(\{b_{n}\}\)的首项是\(-5\),公差为\(1\),把\(\{b_{n}\}\)中的各项按如下规则依次插入到\(\{a_{n}\}\)的每相邻两项之间,构成新数列\(\{c_{n}\}\):\(a_{1}\),\(b_{1}\),\(a_{2}\),\(b_{2}\),\(b_{3}\),\(a_{3}\),\(b_{4}\),\(b_{5}\),\(b_{6}\),\(a_{4}\),\(…\),即在\(a_{n}\)和\(a_{n+1}\)两项之间依次插入\(\{b_{n}\}\)中\(n\)个项,则\(c_{2018}=\) ______ \(.(\)用数字作答\()\)