a-a a-b aaa aab aah aao aar aau aax ab- aba abb abh abo abr abu abx aha ahb ahh aho ahr ahu ahx aoa aob aoh aoo aor aou aox ar- ara arb arh aro arr aru arx au- aua aub auh auo aur aux ax- axa axh axo axr axx b-u baa bab bah bao bar bau bax bba bbb bbh bbo bbr bbu bbx bha bhb bhh bho bhr bhu bhx boa bob boh boo bor bou box bra brb brh bro brr bru brx bua bub buh buo bur buu bux bxb bxo bxx haa hab hah hao har hau hax hba hbb hbh hbo hbr hbu hbx hha hhb hhh hho hhr hhu hoa hob hoh hoo hor hou hox hr- hra hrb hrh hro hrr hru hua hub huh huo hur huu hux oaa oab oah oao oar oau oax ob- oba obb obh obo obr obu obx oha ohh oho ohr ohu oo- ooa oob ooh ooo oor oox or- ora orb orh oro orr oru orx ou- oua ouh ouo our ox- oxa oxb oxo oxx ra- raa rab rah rao rar rau rax rba rbb rbh rbo rbr rbu rbx rh- rha rhb rhh rho rhr rhu roa rob roh roo ror rou rox rra rrb rrh rrr rru rua rub ruh ruo rur ruu rux rxr ua- uaa uab uah uao uar uau uba ubb ubh ubo ubr ubu ubx uha uhb uhh uho uhr uhu uoa uob uoo uor uox ur- ura urb uro urr uru urx uua uur uuu uxb uxo uxr uxu xaa xar xau xbr xbx xoa xoo xor xox xrx xxo xxx