摘要:13.数列{}中.=2..且数列{ }是等差数列.则= .
网址:http://m.1010jiajiao.com/timu_id_1655893[举报]
等差数列{an}的各项均为正整数,a1=3,前n项和为Sn,等比数列{bn}中,b1=1,且b2S2=64,{ban}是公比为64的等比数列.
(1)求{an}与{bn};
(2)证明:
+
+…+
<
.
查看习题详情和答案>>
(1)求{an}与{bn};
(2)证明:
| 1 |
| S1 |
| 1 |
| S2 |
| 1 |
| Sn |
| 3 |
| 4 |