bbb bbc bbm bbn bbo bbs bbt bcb bcc bcm bcn bco bcs bct bmb bmc bmm bmn bmo bms bmt bnb bnc bnn bno bns bnt bob boc bom bon boo bos bot bsb bsc bsm bsn bso bss bst btb btc btm btn bto bts btt c-- cbb cbc cbm cbn cbo cbs cbt ccb ccc ccm ccn cco ccs cct cmb cmc cmm cmn cmo cms cmt cn- cnb cnc cnm cnn cno cns cnt co- cob coc com con coo cos cot csb csc csm csn cso css cst ctb ctc ctm ctn cto cts ctt m-o mbb mbc mbm mbo mbs mbt mc- mcb mcc mcm mcn mco mcs mct mmb mmc mmm mmn mmo mms mmt mnb mnc mnm mnn mno mns mnt mob moc mom mon moo mos mot msb msc msm msn mso mss mst mtb mtc mtm mtn mto mts mtt nbb nbc nbm nbn nbo nbs nbt ncb ncc ncm ncn nco ncs nct nmb nmc nmm nmn nmo nms nmt nnb nnc nnm nnn nno nns nnt no- nob noc nom non noo nos not nsb nsc nsm nsn nso nss nst ntb ntc ntm ntn nto nts ntt ob- obb obc obm obn obo obs obt oc- ocb occ ocm ocn oco ocs oct om- omb omc omm omn omo oms omt on- onb onc onn ono ons ont oo- oob ooc oom oon ooo oos oot os- osb osc osm osn oso oss ost ot- otb otc otm otn oto ots ott sbb sbc sbm sbn sbo sbs sbt scb scc scm scn sco scs sct smb smc smm smn smo sms smt snb snc snm snn sno sns snt sob soc som son soo sos sot ss- ssb ssc ssm ssn sso sss sst stb stc stm stn sto sts stt tbb tbc tbm tbn tbo tbs tbt tcb tcc tcm tcn tco tcs tct tmb tmc tmm tmn tmo tms tmt tnb tnc tnm tnn tno tns tnt to- tob toc tom ton too tos tot tsb tsc tsm tsn tso tss tst ttb ttc ttm ttn tto tts ttt