7.对于数列{an}\{a_{n}\}{an},若a1=1a_{1}=1a1=1,an+an+1=2n(n∈N∗){a}_{n}+{a}_{n+1}=2n(n\in {N}^{*})an+an+1=2n(n∈N∗),则下列说法正确的是((( )))