bbb bbk bbr bbs bbt bby bkb bkk bkr bks bkt brb brk brr brs brt bry brz bsb bsk bsr bss bst bsy btb btk btr bts btt bty btz by- byk byr bys byt byz bzr bzs bzz k-t k-z kbb kbk kbr kbs kbz kkb kkk kkr kks kkt kky krk krr krs krt kry ksb ksk ksr kss kst ktb ktk ktr kts ktt kyr kys kyt kyz kzy rbb rbk rbr rbs rbt rkb rkk rks rkt rky rkz rrb rrk rrr rrs rrt rsb rsk rsr rss rst rtb rtk rtr rts rtt rty rtz ry- ryk ryr rys ryy ryz rzb rzy sbb sbk sbr sbs sbt sby sk- skb skk skr sks skt sky sr- srb srk srr srs srt sry ss- ssb ssk ssr sss sst ssz stb stk str sts stt sty stz sy- syb syk syr sys syt szr tbb tbk tbr tbs tbt tbz tkb tkk tkr tks tkt tky tkz trb trk trr trs trt try trz tsb tsk tsr tss tst tsy ttb ttk ttr tts ttt tty tyr tys tyt tzs ybr ybs yby ybz ykk yrs yrt ysb ysk ysr yss yst ysy ysz ytk ytr yts ytt yyb yys yyt yyy yyz yzb yzr yzy zbb zbr zbs zbt zby zks zrs zst zsz ztr zzr zzs zzt zzy zzz