题目

--- Good morning, this is Dr. Allen’s office. --- Good morning, I’d like to make an appointment with Dr. Allen. I have my teeth cleaned and checked.   1  --- I’ll see whether the doctor has time to see you this week.   2  --- No, I’ve just moved to town and a friend of mine advised me to see him. My name is Edward Johnson. ---   3  . If you are having trouble with your teeth, I’ll work you in, otherwise I can give you an appointment next Friday, the 29 th. Will that be all right? --- I’m sorry.   4   I’m not having any trouble with my teeth, but I had hoped to have 已知数列{an}的前n项和为Sn，且满足Sn＝2an－n，(n＝1，2，3，……) (Ⅰ)求a1，a2，a3的值； (Ⅱ)求证：数列{an＋1}是等比数列； (Ⅲ)若bn＝nan，求数列{bn}的前n项和Tn．