一、数列求和中的拆分技巧此拆分技巧是将n分解为n个1,然后将n项与每一个1相结合,转化为新的数列求和.例1设{an}是正数组成的数列,其前n项和为Sn,并且对于所有的自然数n,an与2的等差中项等于Sn与2的等比中项. Splitting Techniques in Series Summation This splitting technique breaks n down into n 1s, then combines n items with each 1 and converts them into new summations. Example 1 Let {an} be a positive number In the sequence of numbers, the sum of the first n terms is Sn, and for all natural numbers n, the equal-difference term of an and 2 is equal to the equal-ratio of Sn and 2.