设数为xx=3k+1x=5m+2x=7n+3 k,m,n都是整数3k+1=5m+2=7n+3得　k =(5m+1)/3 n= (5m-1)/7因为k,n都是整数,所以 由k =(5m+1)/3得m是3的倍数,令m=3j+1由n= (5m-1)/7得,n= (15j+4)/7 得 j= 7h+3所以x = 5m+2 = 15j+7=105h+...