(1)、规律:1/n*[1/(n+1)]=1/n-1/(n+1)
(2)、
1、1*1/2+1/2*(1/3)+1/3*(1/4)+1/4*(1/5)+1/5*(1/6)+1/6*(1/7)
=1-1/2+1/2-1/3+1/3-1/4+1/4-1/5+1/5-1/6+1/6-1/7
=1-1/7
=6/7
2、[1/4*(1/7)+1/7*(1/10)+1/10*(1/13)+1/13*(1/16)]*3
=(1/4-1/7+1/7-1/10+1/10-1/13+1/13-1/16)/3*3
=1/4-1/16
=3/16