10.
.已知数列\(\{\)\(a_{n}\)\(\}\)的前\(n\)项和为\(S_{n}\),且\(S_{n}=a_{n+}\)\({\,\!}_{1}\)\(+n-\)\(2\),\(n\)\(∈N\)\({\,\!}^{*}\),\(a\)\({\,\!}_{1}\)\(=\)\(2\).
\((1)\)证明:数列\(\{\)\(a_{n}-\)\(1\}\)是等比数列,并求数列\(\{\)\(a_{n}\)\(\}\)的通项公式\(;\)
\((2)\)设\(b_{n}=\)\( \dfrac{3n}{{S}_{n}-n+1} (\)\(n\)\(∈N\)\({\,\!}^{*}\)\()\)的前\(n\)项和为\(T_{n}\),证明:\(T_{n} < \)\(6\).