-ic bbb bbc bbi bbk bbo bbr bcb bcc bci bck bco bcr bi- bib bic bii bik bio bir bkb bkc bkk bko bkr bob boc boi bok boo bor brb bri brk bro brr c-- cbb cbc cbi cbk cbo cbr ccb ccc cci cck cco ccr ci- cib cic cii cik cio cir ckb ckc cki cko co- cob coc coi cok coo cor crb crc cri crk cro crr ibb ibc ibi ibk ibo ibr icb icc ici ick ico icr iib iic iii iio iir ikb ikc iki ikk iko ikr io- iob ioc ioi ioo ior ir- irb irc iri irk iro irr kbb kbc kbi kbk kbo kbr kcb kcc kci kck kcr kib kic kii kik kio kir kkb kkc kki kkk kkr kob koc koi kok koo kor krc kri krk kro krr o-i ob- obb obc obi obk obo obr oc- ocb occ oci ock oco ocr oib oic oii oik oio oir okb okc oki okk oko okr oo- oob ooc ooi ook ooo oor or- orb orc ori ork oro orr rbb rbc rbi rbk rbo rbr rcb rcc rci rco rcr rib ric rii rik rio rir rkb rkc rkk rko rob roc roi rok roo ror rrb rrc rri rrk rrr