[10^(1/2)-20^(1/2)]^2
数字推理 3/10,7/20,(),1/2,1/2
会计上2/10,1/20,
1/2,7/2,7,10,20,(),()
1*2*3+2*4*6+...10*20*30/2*3*4+...+20*30*40
2/1 3/1 4/1 5/1 6/1 8/1 10/1 12/1 15/1 20/1
1/2+1/6+1/12+1/20+1/30+1/42+1/56+1/72+1/90+1/10
(-1)+(-2)+...+(-10)
excel 中 判断正负如 a b c 1 10 20 -10 2 20 10 +10
10/(1*2)+20/(1*2*3)+30/(1*2*3*4)+40/(1*2*3*4*5)+...+90/(1*2*
10/(1*2)+20/(1*2*3)+30/(1*2*3*4)+40/(1*2*3*4*5)++...+90/(1*2
1 1 1 1 2 1 1 3 3 1 1 4 6 4 1 1 5 10 10 5 1 1 6 15 20 15 6 1
现金折扣条件2/10-1/20-N/30,