The A numbers are form (1~8). Organize the B numbers (1~8) according to the following rules: 1- The B numbers can not be repeated. 2- Add A and B so there will be no repeating results. 3- Subtract A and B so the answers will not be duplicated. Example: A= 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 B= 3 , 5 , 2 , 8 , 1 , 7 , 4 , 6 (A+ (A- 1+3=4 1-3=-2 2+5=7 2-5=-3 3+2=5 3-2= 1 4+8=12 4-8=-4 5+1=6 5-1= 4 6+7=13 6-7=-1 7+4=11 7-4= 3 8+6=14 8-6= 12 Can you find any formula for this? How many series of B can you find?