1/(100*101)+1/(101*102)+……+1/n(n+1)
=(1/100-1/101)+(1/101-1/102)+(1/102-1/103)+.+[1/n-1/(n+1)]
=1/100-1/(n+1)
所以1/100-1/(n+1)=1907/200700
1/(n+1)=100/200700
n+1=2007
n=2006
1/(100*101)+1/(101*102)+……+1/n(n+1)
=(1/100-1/101)+(1/101-1/102)+(1/102-1/103)+.+[1/n-1/(n+1)]
=1/100-1/(n+1)
所以1/100-1/(n+1)=1907/200700
1/(n+1)=100/200700
n+1=2007
n=2006