已知数列{an}的前n项和为Sn,对一切正整数n,点Pn(n,Sn)都在偶函数f(x)=x2+bx的图像上.
(1)求数列{an}的通项公式;
(2)若bn=2n+an,求数列{bn}的前n项和Tn.
(1)an=2n-1 (2)Tn=2n+1+n2-2