Level 2 -------- AABXYA Level 3 -------- XAYAAB Level 4 -------- YYBAXA Level 5 -------- BABXXY Level 6 -------- XAXBYY Level 7 -------- ABXBYB Level 8 -------- YBBAXY Level 9 -------- BYAAXB Level 10 ------- XABBAX Level 11 ------- YBYXAB Level 12 ------- XBAXBY