a-a a-b a-i a-t aaa aab aai aak aar aat ab- aba abb abi abk abr abt ai- aia aib aii aik air ait aka akb aki akk akr ar- ara arb ari ark arr art at- ata atb ati atr att baa bab bai bak bar bat bba bbb bbi bbk bbr bbt bi- bia bib bii bik bir bit bka bkb bkk bkr bkt bra brb bri brk brr brt bta btb bti btk btr btt ia- iaa iab iai iar iat iba ibb ibi ibk ibr ibt iia iib iii iir iit ika ikb iki ikk ikr ikt ir- ira irb iri irk irr irt ita itb iti itk itt k-t ka- kaa kab kai kak kar kat kba kbb kbi kbk kbr kia kib kii kik kir kit kkb kki kkk kkr kkt kra kri krk krr krt kta ktb ktk ktr ktt ra- raa rab rai rak rar rat rba rbb rbi rbk rbr rbt ria rib rii rik rir rit rkb rkk rkt rra rrb rri rrk rrr rrt rta rtb rti rtk rtr rtt taa tab tai tak tar tat tba tbb tbi tbk tbr tbt tia tib tii tik tir tit tka tkb tkk tkr tkt tra trb tri trk trr trt tta ttb tti ttk ttr ttt