8/1+15/1+24/1+```````+143/1

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8/1+15/1+24/1+```````+143/18/1+15/1+24/1+```````+143/18/1+15/1+24/1+```````+143/1首先题目应该写成1/8+1/15+1/

8/1+15/1+24/1+```````+143/1
8/1+15/1+24/1+```````+143/1

8/1+15/1+24/1+```````+143/1
首先题目应该写成1/8+1/15+1/24+……+1/143
1/8+1/15+1/24+……+1/143
=1/(2*4)+1/(3*5)+(4*6)+……+1/(11*13)
=1/2*[1/2-1/4+1/3-1/5+1/4-1/6+……+1/11-1/13]
=1/2*(1/2+1/3-1/12-1/13)
=105/256

(a*a-1)/1+....(a*a-1)/1
其中a=3,4,5.....12