[重点]主攻274916头,主攻274916尾.
1,排除053头,160百,165十,380尾.
2,铁卒:43,48,93,89.
3,三字现:431,436,481,486,931,936,981,986.
4,二定:4XX2,4XX7,9XX2,9XX7,XX42,XX47,XX92,XX97,4X4X,4X9X
5,三定:4X42,4X47.4X92,4X97,9X42,9X47,9X92,9X97,X342,X347.
6,直码:4342,4347,4392,4397,4842,4847,4892,4897,9342,9347.