bbb bbc bbe bbk bbm bbo bbt bcb bcc bce bck bcm bco bct be- beb bec bee bek bem beo bet bkb bkc bke bkk bkm bko bkt bmb bmc bme bmk bmm bmo bmt bob boc boe bok bom boo bot btb btc bte btk btm bto btt c-- cbb cbc cbe cbk cbm cbo cbt ccb ccc cce cck ccm cco cct ce- ceb cec cee cek cem ceo cet ckb ckc ckm cko ckt cmb cmc cme cmk cmm cmo cmt co- cob coc coe cok com coo cot ctb ctc cte ctk ctm cto ctt ebb ebc ebe ebk ebm ebo ebt ec- ecb ecc ece eck ecm eco ect eeb eec eee eek eem eeo eet ekb ekc eke eko ekt em- emb emc eme emk emm emo emt eo- eob eoc eoe eok eom eoo eot etb etc ete etk etm eto ett k-t kbb kbc kbe kbk kbm kbo kcb kcc kce kck kcm kct ke- keb kec kee kek kem keo ket kkb kkc kke kkk kkm kkt kmb kmc kme kmk kmm kmo kmt kob koc koe kok kom koo kot ktb ktc kte ktk ktm kto ktt m-o mbb mbc mbe mbk mbm mbo mbt mc- mcb mcc mce mck mcm mco mct meb mec mee mek mem meo met mkb mkc mke mkk mkm mko mkt mmb mmc mme mmk mmm mmo mmt mob moc moe mok mom moo mot mtb mtc mte mtk mtm mto mtt ob- obb obc obe obk obm obo obt oc- ocb occ ock ocm oco oct oeb oec oee oem oeo oet okb okc oke okk oko om- omb omc ome omm omo omt oo- oob ooc ook oom ooo oot ot- otb otc ote otk otm oto ott tbb tbc tbe tbk tbm tbo tbt tcb tcc tce tck tcm tco tct te- teb tec tee tek tem teo tet tkb tkc tke tkk tkm tko tkt tmb tmc tme tmk tmm tmo tmt to- tob toc toe tok tom too tot ttb ttc tte ttk ttm tto ttt