数列如下:A1=2,A2=5,A3=11,A4=19,A5=30,A6=44,A7=62 请问
A1+A3+A5+A7=4,求A2+A4+A6
设数列ai>0.且a1+a2+a3+a4+a5+a6+a7+a8+a9+a10=30,a1*a2*a3*a4*a5*a6
a2*a6=4,求a1*a2*a3*a4*a5*a6*a7
a1=8,a7=5832,a1/a2=a2/a3=a3/a4=a4/a5=a5/a6=a6/a7,求a5的值
已知集合A={a1,a2,a3,a4,a5,a6,a7},A并上B={a1,a2,a3,a4,a5,a6,a7,.,a1
(1)a1+a2+a3=30 a4+a5+a6=80 则a7+a8+a9=?
已知一列数a1,a2,a3,a4,a5,a6,a7,且a1=1,a7=729,a1/a2=a2/a3=a3/a4=a4/
已知集合A={a1,a2,a3,a4,a5,a6,a7},A∪B={a1,a2,a3,a4,a5,a6,a7.,a100
等比数列,a1+a2+a3=6,a2+a3+a4=3,求a3+a4+a5+a6+a7+a8=?
已知数列an为等比数列,a1+a2+a3+a4=1,a5+a6+a7+a8=2,则a17+a18+19+a20=
a1+a2+a3=30.a4+a5+a6=80.a7+a8+a9=?
等比数列,a1+a4+a7=23,a2+a5+a8=29,a3+a6+a9=