写出下面数列的前5项 a1=-1 a2=-2 ,an+2=1/an+1 + 1/an

问题描述:

写出下面数列的前5项 a1=-1 a2=-2 ,an+2=1/an+1 + 1/an

a3=-3/2,a4=-7/6,a5=-32/21

-1,-2,-3/2,-7/6,-32/21

a3=1/a2+1/a1=-1/2-1/1=-3/2
a4=1/a3+1/a2=-2/3-1/2=-7/6
a5=1/a4+1/a3=-6/7-2/3=-18/21-14/21=-32/21