3.5.9.17.___._____.129
问题描述:
3.5.9.17.___._____.129
(2) 2/1.4/4.6/9.8/16._____._____.14/49.
答
(1)3.5.9.17.__33_.___65__.129
3*2-1=5
5*2-1=9
…………
(2) 2/1.4/4.6/9.8/16._10/25____._12_/36___.14/49.
分子是2,4,6,8,10,12,14
分母是1*1 2*2 3*3 4*4 5*5 6*6 7*7