-ey bbb bbc bbe bbk bbo bbt bby bcb bcc bce bck bco bct bcy be- beb bec bee bek beo bet bey bkb bkc bke bkk bko bkt bob boc boe bok boo bot boy btb btc bte btk bto btt bty by- byc bye byk byo byt c-- cbb cbc cbe cbk cbo cbt cby ccb ccc cce cck cco cct ce- ceb cec cee cek ceo cet cey ckb ckc cko ckt cky co- cob coc coe cok coo cot coy ctb ctc cte ctk cto ctt cty cyb cyc cye cyk cyo cyt ebb ebc ebe ebk ebo ebt eby ec- ecb ecc ece eck eco ect eeb eec eee eek eeo eet eey ekb ekc eke eko ekt eky eo- eob eoc eoe eok eoo eot etb etc ete etk eto ett ety eyc eye eyo eyt k-t kbb kbc kbe kbk kbo kcb kcc kce kck kct ke- keb kec kee kek keo ket key kkb kkc kke kkk kkt kky kob koc koe kok koo kot koy ktb ktc kte ktk kto ktt kyc kye kyo kyt ob- obb obc obe obk obo obt oby oc- ocb occ ock oco oct oeb oec oee oeo oet oey okb okc oke okk oko oo- oob ooc ook ooo oot ot- otb otc ote otk oto ott oye oyo tbb tbc tbe tbk tbo tbt tcb tcc tce tck tco tct te- teb tec tee tek teo tet tey tkb tkc tke tkk tko tkt tky to- tob toc toe tok too tot toy ttb ttc tte ttk tto ttt tty tyc tye tyo tyt ybc ybe yby ycc yce yco ycy yeb yec yee yek yeo yet yey ykk yob yoc yoe yok yoo yot yoy ytc yte ytk yto ytt yyb yyc yye yyt yyy