a-a a-b a-t aaa aab aae aak aao aap aas aat ab- aba abb abe abk abo abp abs abt aea aeb aee aek aeo aep aes aet aka akb ake akk ako akp aks aoa aob aoe aok aoo aop aos aot ap- apa apb ape apk apo app aps apt as- asa asb ase ask aso asp ass ast at- ata atb ate ato atp ats att b-p baa bab bae bak bao bap bas bat bba bbb bbe bbk bbo bbp bbs bbt be- bea beb bee bek beo bep bes bet bka bkb bke bkk bko bkp bks bkt boa bob boe bok boo bop bos bot bpa bpb bpe bpo bpp bps bpt bsa bsb bse bsk bso bsp bss bst bta btb bte btk bto btp bts btt eaa eab eae eak eao eap eas eat eba ebb ebe ebk ebo ebp ebs ebt eea eeb eee eek eeo eep ees eet eka ekb eke eko ekp eks ekt eo- eoa eob eoe eok eoo eop eos eot ep- epa epb epe epo epp eps ept es- esa esb ese esk eso esp ess est eta etb ete etk eto etp ets ett k-t ka- kaa kab kae kak kao kap kas kat kba kbb kbe kbk kbo kbp kbs ke- kea keb kee kek keo kep kes ket kkb kke kkk kkp kks kkt koa kob koe kok koo kop kos kot kpa kpe kpk kpo kpp kps kpt ksa ksb kse ksk kso ksp kss kst kta ktb kte ktk kto ktp kts ktt oaa oab oae oak oao oap oas oat ob- oba obb obe obk obo obp obs obt oea oeb oee oeo oep oes oet oka okb oke okk oko okp oks oo- ooa oob ook ooo oop oos oot op- opa opb ope opk opo opp ops opt os- osa osb ose osk oso osp oss ost ot- ota otb ote otk oto otp ots ott p-p paa pab pae pak pao pap pas pat pba pbb pbe pbk pbo pbp pbs pbt pea peb pee pek peo pep pes pet pka pkb pke pko pkp pks pkt poa pob poe pok poo pop pos pot ppa ppb ppe ppk ppo ppp pps ppt ps- psa psb pse psk pso psp pss pst pt- pta ptb pte ptk pto ptp pts ptt saa sab sae sak sao sap sas sat sba sbb sbe sbk sbo sbp sbs sbt se- sea seb see sek seo sep ses set sk- ska skb ske skk sko skp sks skt soa sob soe sok soo sop sos sot spa spb spe spk spo spp sps spt ss- ssa ssb sse ssk sso ssp sss sst sta stb ste stk sto stp sts stt taa tab tae tak tao tap tas tat tba tbb tbe tbk tbo tbp tbs tbt te- tea teb tee tek teo tep tes tet tka tkb tke tkk tko tkp tks tkt to- toa tob toe tok too top tos tot tpa tpb tpe tpk tpo tpp tps tpt tsa tsb tse tsk tso tsp tss tst tta ttb tte ttk tto ttp tts ttt