写出下面数列的前5项:a1=-1,a2=-2,a(n+2)=1/a(n+1)+1/an

问题描述:

写出下面数列的前5项:a1=-1,a2=-2,a(n+2)=1/a(n+1)+1/an

这个还能怎么样,一个一个死推啊……
a3=-3/2
a4=-7/6
a5=-32/21

a1=-1
a2=-2
a3= 1/a2 +1/a1 = - 1/2 -1 =-3/2
a4= 1/a3 +1/a2 = -2/3 - 1/2 = -7/6
a5= 1/a4 +1/a3 = -6/7 - 2/3 = -32/21