-al -ol a-a a-b a-c aaa aab aac aal aao aax ab- aba abb abc abl abo abx ac- aca acb acc acl aco acx al- ala alb alc all alo alx aoa aob aoc aol aoo aox ax- axa axl axo axx baa bab bac bal bao bax bba bbb bbc bbl bbo bbx bca bcb bcc bcl bco bcx bla blb blc bll blo blx boa bob boc bol boo box bxb bxl bxo bxx c-- caa cab cac cal cao cax cba cbb cbc cbl cbo cbx cca ccb ccc ccl cco ccx cl- cla clb clc cll clo clx co- coa cob coc col coo cox cxc cxl cxo cxx la- laa lab lac lal lao lax lba lbb lbc lbl lbo lbx lca lcb lcc lcl lco lcx lla llb llc lll llo loa lob loc lol loo lox lxc lxo lxx oaa oab oac oal oao oax ob- oba obb obc obl obo obx oc- oca ocb occ ocl oco ocx ola olb olc oll olo oo- ooa oob ooc ool ooo oox ox- oxa oxb oxc oxo oxx xaa xac xal xbc xbl xbx xcb xcl xcx xla xlb xoa xoc xoo xox xxl xxo xxx