bbbb bbci bcbc bccc bcci bcit bctc bibb bibi bibo bicc bici bico bio- bioc bioi biot bitc bito bitt bobb bobi bobo boco boi- boii boit boob booc boot botb boti boto bott btcc btob bttb c-bo cbbc cbcc cbct cbit cbot cbtc ccbc cccb cccc ccci ccic ccii ccob ccoc cctb cctc cctt cibc cibi cibo cicc cici cico cict ciii ciit ciob citb citi cito citt cobb cobi cobo coco coct coit coob coot cotb cotc coti coto cott ctbi ctic ctot ibot ibtb ibtc icbc iccb iccc icci icco icct icoc iiii iiio iiit iioi iioo iitt iobi ioci ioii ioio ioit iooi iooo ioto itic itoi itoo itto obbo obit oboi obot ocbc occc occi occt oct- octi octo oici oiii oitc oiti oobi oooo ootb otic otit oto- otoo otti otto tbcb tbcc tbit tccc tctc tibi ticc tico tiit titc titi tito titt tobi tobo tobt toci toco toit toot totc toti toto tott ttbb tttt