bbb bbn bbo bbr bbs bbt bnb bnn bno bnr bns bnt bob bon boo bor bos bot brb brn bro brr brs brt bsb bsn bso bsr bss bst btb btn bto btr bts btt nbb nbn nbo nbr nbs nbt nnb nnn nno nns nnt no- nob non noo nor nos not nrb nrn nro nrr nrs nrt nsb nsn nso nsr nss nst ntb ntn nto ntr nts ntt ob- obb obn obo obr obs obt on- onb onn ono onr ons ont oo- oob oon ooo oor oos oot or- orb orn oro orr ors ort os- osb osn oso osr oss ost ot- otb otn oto otr ots ott rbb rbn rbo rbr rbs rbt rnb rnn rno rnr rns rnt rob ron roo ror ros rot rrb rrn rrr rrs rrt rsb rsn rso rsr rss rst rtb rtn rto rtr rts rtt sbb sbn sbo sbr sbs sbt snb snn sno snr sns snt sob son soo sor sos sot sr- srb srn sro srr srs srt ss- ssb ssn sso ssr sss sst stb stn sto str sts stt tbb tbn tbo tbr tbs tbt tnb tnn tno tnr tns tnt to- tob ton too tor tos tot trb trn tro trr trs trt tsb tsn tso tsr tss tst ttb ttn tto ttr tts ttt