数列{An}满足A3=7,A5+A7=26另Bn=2的n次方乘以An求数列Bn前N项和
已知等差数列{an}满足∶a3=7,a5+a7=26,{an}的前几项和为sn令bn=2的n次方乘an,求数列前n项和T
已知等差数列{an}满足:a3=7,a5+a7=26.若bn=an+2的an-1次方,求数列{bn}的前n项和Sn
等差数列{an}的前n项和为Sn,满足a3=7,且a5+a7=26,求:令bn=1∕(an²-4﹚,求数列bn
已知数列an中 a3+a5=10 an的前n项和为sn s5=15 设bn=(1/2)的n次方an 求数列bn的前n项和
设数列{bn}的前n项和为sn,且bn=2-2sn;数列{an}为等差数列,且a5=14,a7=20求
已知等差数列{an}满足:a3=7,S11=143 ,令bn=2^an(N属于N*),求数列{bn}的前n项和Tn
设数列Bn的前n项和为Sn,且Bn=2-2Sn.数列An为等差数列,且A5=10,A7=14.(1)求数列An、{bn}
已知数列an,的通项公式为an=2n,且bn=an乘以3n次方,求bn前n项和
1.已知等差数列{an}满足a3=7,a5+a7=26,数列的前n项和为Sn令bn=1/(an²-1) &nb
设数列{Bn}的前n项和为Sn,且Bn=2-2Sn;数列{An}为等差数列,且A5=14,A7=20.
设数列{bn}的前n项和为Sn,且bn=2-2s.数列{an}为等差数列,且a5=14,a7=20.
设数列{bn}的前n项和为Sn,且bn=2-2Sn,数列{an}为等差数列,且a5=14,a7=20