-er a-a a-b a-c a-t aaa aab aac aad aae aak aao aap aar aat ab- aba abb abc abd abe abk abo abp abr abt ac- aca acb acc acd ace ack aco acp acr act ad- ada adb adc add ade adk ado adp adr adt aea aeb aec aed aee aek aeo aep aer aet aka akb akc akd ake akk ako akp akr aoa aob aoc aod aoe aok aoo aop aor aot ap- apa apb apc apd ape apk apo app apr apt ar- ara arb arc ard are ark aro arp arr art at- ata atb atc atd ate ato atp atr att b-p baa bab bac bad bae bak bao bap bar bat bba bbb bbc bbd bbe bbk bbo bbp bbr bbt bca bcb bcc bcd bce bck bco bcp bcr bct bda bdb bdc bdd bde bdk bdo bdp bdr bdt be- bea beb bec bed bee bek beo bep ber bet bka bkb bkc bke bkk bko bkp bkr bkt boa bob boc bod boe bok boo bop bor bot bpa bpb bpc bpd bpe bpo bpp bpr bpt bra brb brd bre brk bro brp brr brt bta btb btc btd bte btk bto btp btr btt c-- caa cab cac cad cae cak cao cap car cat cba cbb cbc cbd cbe cbk cbo cbp cbr cbt cca ccb ccc ccd cce cck cco ccp ccr cct cda cdb cdc cdd cde cdk cdo cdp cdr cdt ce- cea ceb cec ced cee cek ceo cep cer cet cka ckb ckc ckd cko ckt co- coa cob coc cod coe cok coo cop cor cot cpa cpb cpc cpd cpe cpk cpo cpp cpr cpt cra crb crc crd cre crk cro crp crr crt cta ctb ctc ctd cte ctk cto ctp ctr ctt daa dab dac dad dae dak dao dap dar dat dba dbb dbc dbd dbe dbk dbo dbp dbr dbt dca dcb dcc dcd dce dck dco dcp dcr dct dda ddb ddc ddd dde ddk ddo ddp ddr ddt de- dea deb dec ded dee dek deo dep der det dka dkb dkc dke dkk dko dkp dkr dkt doa dob doc dod doe dok doo dop dor dot dpa dpb dpc dpd dpe dpk dpo dpp dpr dpt dra drb drc drd dre drk dro drp drr drt dta dtb dtc dtd dte dtk dto dtp dtr dtt eaa eab eac ead eae eak eao eap ear eat eba ebb ebc ebd ebe ebk ebo ebp ebr ebt ec- eca ecb ecc ecd ece eck eco ecr ect ed- eda edb edc edd ede edk edo edp edr edt eea eeb eec eed eee eek eeo eep eer eet eka ekb ekc ekd eke eko ekp ekr ekt eo- eoa eob eoc eod eoe eok eoo eop eor eot ep- epa epb epc epd epe epo epp epr ept era erb erc erd ere erk ero erp err ert eta etb etc etd ete etk eto etp etr ett k-t ka- kaa kab kac kad kae kak kao kap kar kat kba kbb kbc kbd kbe kbk kbo kbp kbr kca kcb kcc kcd kce kck kcp kcr kct kda kdb kdc kde kdk kdo kdp kdr kdt ke- kea keb kec ked kee kek keo kep ker ket kkb kkc kke kkk kkp kkr kkt koa kob koc kod koe kok koo kop kor kot kpa kpc kpd kpe kpk kpo kpp kpr kpt kra krc krd krk kro krp krr krt kta ktb ktc kte ktk kto ktp ktr ktt oaa oab oac oad oae oak oao oap oar oat ob- oba obb obc obd obe obk obo obp obr obt oc- oca ocb occ ocd ock oco ocp ocr oct oda odb odc odd ode odo odp odr odt oea oeb oec oed oee oeo oep oer oet oka okb okc okd oke okk oko okp okr oo- ooa oob ooc ood ook ooo oop oor oot op- opa opb opc opd ope opk opo opp opr opt or- ora orb orc ord ore ork oro orp orr ort ot- ota otb otc otd ote otk oto otp otr ott p-p paa pab pac pad pae pak pao pap par pat pba pbb pbc pbd pbe pbk pbo pbp pbr pbt pca pcb pcc pcd pce pck pco pcp pcr pct pda pdb pdc pdd pde pdk pdo pdp pdr pdt pea peb pec ped pee pek peo pep per pet pka pkb pkc pkd pke pko pkp pkr pkt poa pob poc pod poe pok poo pop por pot ppa ppb ppc ppd ppe ppk ppo ppp ppr ppt pra prb prc prd pre prk pro prp prr prt pt- pta ptb ptc ptd pte ptk pto ptp ptr ptt ra- raa rab rac rad rae rak rao rap rar rat rba rbb rbc rbd rbe rbk rbo rbp rbr rbt rca rcb rcc rcd rce rco rcp rcr rct rda rdb rdc rdd rde rdo rdp rdr rdt re- rea reb rec red ree rek reo rep rer ret rkb rkc rke rkk rko rkp rkt roa rob roc rod roe rok roo rop ror rot rpa rpb rpc rpd rpe rpk rpo rpp rpr rpt rra rrb rrc rrd rrk rrp rrr rrt rta rtb rtc rtd rte rtk rto rtp rtr rtt taa tab tac tad tae tak tao tap tar tat tba tbb tbc tbd tbe tbk tbo tbp tbr tbt tca tcb tcc tcd tce tck tco tcp tcr tct tda tdb tdc tdd tde tdk tdo tdp tdr tdt te- tea teb tec ted tee tek teo tep ter tet tka tkb tkc tke tkk tko tkp tkr tkt to- toa tob toc tod toe tok too top tor tot tpa tpb tpc tpd tpe tpk tpo tpp tpr tpt tra trb trc trd tre trk tro trp trr trt tta ttb ttc ttd tte ttk tto ttp ttr ttt