题目内容：

/2*5+1/5*8+1/8*11+...+1/2003*2006

优质解答

=1/3*((1/2-1/5)+(1/5-1/8)+(1/8-1/11)+...+1/2003-1/2006)
=1/3*(1/2-1/2006)
=1/3*(501/1003)
=167/1003