根据级数收敛的必要条件,如果级数收敛,则n趋于无穷时一般项趋于0,所以lim(an-a(n+1))=0,即liman=lima(n+1)。又因为和为S,所以n趋于无穷时,S=lim(a1-d2+a2-a3+...+an-a(n+1))=lim(a1-a(n+1)),所以liman=lima(n+1)=a1-S
和式=a1-a2+a2-a3+……+an-an+1=a1-an+1=S(a后面均为下标)
∴an+1=a1-s
lim(n趋于无穷大)an=lim(n趋于无穷大)an+1=a1-s
答案是:
0