1+1/(1+2)+1/(1+2+3)+1/(1+2+3+4)+……+1/(1+2+3+4+……+2007)=2/1*2 +2/2*3 +2/3*4 +2/4*5 +……＋2/2007*2008=2*(1/1-1/2 +1/2 -1/3+1/3-1/4+1/4-1/5+……＋1/2007－1/2008）=2*(1-1/2008)=4014/2008=2007/1004...
1+1/(1+2)+1/(1+2+3)+1/(1+2+3+4)+……+1/(1+2+3+4+……+2007)
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