设等差数列{an}的前n项和为Sn,且a2=4,S5=30.数列{bn}满足b1=0,bn=2bn-1+1,(n∈N,n≥2), ①求数列{an}的通项公式; ②设Cn=bn+1,求证:{Cn}是等比数列,且{bn}的通项公式; ③设数列{dn}满足dn=+bn,求{dn}的前n项和为Tn. |
与“设等差数列{an}的前n项和为Sn,且a2=4,S5=30.数列{bn}满足b1=0,bn=2bn-1+1,(n∈N,n≥2),①求数列{an}的通项公式;②设Cn=bn+1,求证:{Cn}是等比数列,且{bn}的通项公式;③设”考查相似的试题有: