所谓“递归法”是通过确立一个序列相邻各项之间的一般关系以及初始值来确定序列通项或整个序列的思维方法.其思维程序是:①找出该序列的第一项或前几项;②找到一个或几个关系式,使序列中的一般项与它的相邻前几项联系起来;③通过变换等方法求出更为基本的关系式,从而用递推的 The so-called “recursive method” is a method of thinking that determines the general term or the entire sequence of a sequence by establishing a general relationship between the adjacent items of the sequence and the initial value. The thinking process is: 1 Find out the first or previous of the sequence. Several; 2 find one or more relations, the general terms of the sequence and its adjacent first few items are linked together; 3 through the transformation and other methods to find a more basic relationship, so as to use recursive