A：设计是技术发展的重要驱动力
B：技术的发展与设计无关
C：技术的发展对设计不产生影响
D：技术的丰富内涵
We go shopping on Sunday. My father likes fruits very much. We buy some bananas and red apples at the fruit shop. My mother likes to wear new clothes. She buys a new sweater and a new skirt at the clothes shop. I buy three books at the book shop. At last(最后)，we buy some tea for my grandfather in a tea shop.
分子很小，看不见摸不着，但我们可以通过一些现象来认识它．如“满架蔷薇一院香”说明 ____；铅笔很难被拉断说明 ____
①若{an}是“等方差数列”，则数列{an2}是等差数列；
②{（﹣1）n}是“等方差数列”；
③若{an}是“等方差数列”，则数列{akn}（k∈N*，k为常数）不可能还是“等方差数列”；
④若{an}既是“等方差数列”，又是等差数列，则该数列是常数列．
其中正确的结论是____．（写出所有正确结论的编号）
