243期：01,03,06,08,09,10,11,12,14,15,17,20,21,22,23,24,25,26,31,32,33,35,36,39,42,43,45,47··（共半数）开21准
244期：01,04,05,06,09,10,16,17,18,22,23,24,25,28,29,30,34,35,38,39,40,41,42,43,44,45,48,49··（共半数）开46错
245期：01,02,03,07,09,10,12,15,16,17,20,21,23,27,28,30,31,33,34,36,38,40,42,43,46,47,48,49··（共半数）开？？！