5-1=4 9-2=7 14-3=11 20-4=16
然后7-4=3 11-7=4 16-11=5
推得后面22-16=6 则5+22=27
所以是5和27
更简单的:错开来看分两排1,2,3,4,5`````都差1
5,9,14,20,27 `````差4,5,6,7````