已知数列{an}满足a1=1,a2=3,an+2=3an+1-2an求an
已知数列{an}满足a1=1,a2=3,an+2=3an+1-2an求an
已知数列an满足a1=1.a2=3,an+2=3an+1-2an
已知数列{an}满足a1=1,an=a1+1/2a2+1/3a3+...+1/n-1an-1(n>1)求数列{an}的通
数列{an}满足a1=1,且an=an-1+3n-2,求an
已知数列{an}中,a1=-1,a2=4,an+2+2an=3an+1 求证:数列{an+1-an}是等比数列,并求{a
已知数列{an}满足a1=1/2,an+1=3an+1,求数列{an}通项公式
已知数列{an}满足an+1=2an+3.5^n,a1=6.求an
已知数列an满足an=1+2+...+n,且1/a1+1/a2+...+1/an
已知数列an满足 a1=1/2,an+1=3an/an+3求证1/an为等差数列
已知数列(an)满足an+1=2an+3×2∧n,a1=2求an
数列{an}满足 a1=2,a2=5,an+2=3an+1-2an.(1)求证:数列{an+1-an}是等比数列; (2
已知数列{an}满足:a1=1,且an-an-1=2n,求(1)a2,a3,a4.(2)求数列{an}的通项an