已知\(S_{n}\)为数列\(\{ a_{n}\}\)的前\(n\)项和,\(a_{1}{=}a_{2}{=}1\),平面内三个不共线的向量\(\overrightarrow{{OA}}{,}\overrightarrow{{OB}}{,}\overrightarrow{{OC}}\),满足\(\overrightarrow{{OC}}{=}(a_{n{-}1}{+}a_{n{+}1})\overrightarrow{{OA}}{+}(1{-}a_{n})\overrightarrow{{OB}}{,}n{\geqslant }2{,}n{∈}N^{{*}}\),若\(A{,}B{,}C\)在同一直线上,则\(S_{2018}{=}\)______.