bbbb bbci bbeb bbrc bcbc bccc bcci bcec bcer bcie bebb bebe bebi beci beck beeb beek beer beic beik beir beke beki berc bere beri berk berr bibb bibe bibi bicc bice bici bick bieb bier bike birb bire biri birk birr brcb brce breb brec bree brei brek brer bric brie brik brkb brrr cbbc cbcc cbce cbcr cbec cbee cber cbir cbkr cbre ccbc cccb cccc ccci ccee ccic ccii ccir ccrc ccre ccri cec- cece ceci ceeb ceec ceke cer- cerc cere ceri cibc cibe cibi cicc cici cicr ciee cier ciii cikr cirb circ cire ciri cirk cirr ckbc ckbe ckbi ckck cker ckrc crbc crcc crce crcr cre- creb crec cree crei crib cric crie crik crkc ebbc ebbr ebcc eber ebic ecbc ecbe eccb eccc ecce ecci ecib ecrc ecri ecrr eeee eeke eerc eick eiec eiei eier eike eiki eire ekeb ekek eker ekki erbb erbe ercc erce ereb erec erei erer eric erie erik erke erki errc erre i-be ibec ibie ibrc ibri icbc iccb iccc icci iccr icec icee icer icke icrc icre icrr iecc ieie iere ieri iiie iiii iirc ikee iker ikki ikri irbe ircc iree irer iri- iric irie irki irrc irre irri k-ci kbbb kbbc kbbe kbbi kbbk kbbr kbcb kbce kbci kbck kbcr kbeb kbec kbee kbek kber kbib kbic kbie kbik kbkb kbkk kbkr kbrb kbrc kbre kbri kbrk kcbc kcbi kcbk kcbr kccb kccc kcci kcck kccr kceb kcec kcee kcei kcic kcie kcii kcir kckc kckk kckr kcrc kcri kcrr kebb kebc kebe kebi kebr keck kecr keek keer keib keii keik keir kekb kekc keke keki ker- kerb kerc kere keri kerk kerr kibb kibc kibe kibi kibr kicb kicc kice kick kicr kier kiic kiii kiik kikc kiki kikk kikr kirb kirc kiri kirk kirr kkbb kkbe kkbi kkbr kkcb kkci kkck kkcr kkic kkik kkkk kkrb kkrc kkre kkrk kkrr krbb krbe krbi krbk krbr krcb krcc krce krci kreb krec kree krei krek krib krik krkc krke krki krkk krkr krrb krrc krre krri krrk krrr rbbb rbbr rcbc rccb rccc rcic rebb rebe rebk recc rece reci reck recr reeb reek reii reik reir reke reki rere reri rib- ribe ricc rice rick riek rier rike riki rikk rire riri rrrr