a-a a-b a-c a-t aaa aab aac aak aao aap aat ab- aba abb abc abk abo abp abt ac- aca acb acc ack aco acp act aka akb akc akk ako akp aoa aob aoc aok aoo aop aot ap- apa apb apc apk apo app apt at- ata atb atc ato atp att b-p baa bab bac bak bao bap bat bba bbb bbc bbk bbo bbp bbt bca bcb bcc bck bco bcp bct bka bkb bkc bkk bko bkp bkt boa bob boc bok boo bop bot bpa bpb bpc bpo bpp bpt bta btb btc btk bto btp btt c-- caa cab cac cak cao cap cat cba cbb cbc cbk cbo cbp cbt cca ccb ccc cck cco ccp cct cka ckb ckc cko ckt co- coa cob coc cok coo cop cot cpa cpb cpc cpk cpo cpp cpt cta ctb ctc ctk cto ctp ctt k-t ka- kaa kab kac kak kao kap kat kba kbb kbc kbk kbo kbp kca kcb kcc kck kcp kct kkb kkc kkk kkp kkt koa kob koc kok koo kop kot kpa kpc kpk kpo kpp kpt kta ktb ktc ktk kto ktp ktt oaa oab oac oak oao oap oat ob- oba obb obc obk obo obp obt oc- oca ocb occ ock oco ocp oct oka okb okc okk oko okp oo- ooa oob ooc ook ooo oop oot op- opa opb opc opk opo opp opt ot- ota otb otc otk oto otp ott p-p paa pab pac pak pao pap pat pba pbb pbc pbk pbo pbp pbt pca pcb pcc pck pco pcp pct pka pkb pkc pko pkp pkt poa pob poc pok poo pop pot ppa ppb ppc ppk ppo ppp ppt pt- pta ptb ptc ptk pto ptp ptt taa tab tac tak tao tap tat tba tbb tbc tbk tbo tbp tbt tca tcb tcc tck tco tcp tct tka tkb tkc tkk tko tkp tkt to- toa tob toc tok too top tot tpa tpb tpc tpk tpo tpp tpt tta ttb ttc ttk tto ttp ttt