a1=1,an+1=3an+2,求an
数列{an},a1=1,an+1=2an-n^2+3n,求{an}.
a1=1 an+1=an/2an+3,用两种方法求an
数列{an}满足a1=1,且an=an-1+3n-2,求an
a1=3,an=2an-1+3 证{an+3}等比,并求an
在等差数列an中,a1=2,3an+1-an=0,求an
已知等差数列{an}中,a1=2.an+1=an+3分之an 求an
已知数列{an}满足a1=1,a2=3,an+2=3an+1-2an求an
在数列an中,a1=2,an+1=an/an+3,求an 麻烦讲得详细点
数列an中,a1=3,an+1=an/2an+1,则an=?
已知a1=2,an不等于0,且an+1-an=2an+1an,求an
a1=1/2,an+1=an/an+2,求n/an的sn
已知{an}中a1=1 且an+1=3an+4求an