-er a-a a-b a-i a-t aaa aab aae aai aao aap aar aas aat ab- aba abb abe abi abo abp abr abs abt aea aeb aee aei aeo aep aer aes aet ai- aia aib aie aii aio aip air ais ait aoa aob aoe aoi aoo aop aor aos aot ap- apa apb ape api apo app apr aps apt ar- ara arb are ari aro arp arr ars art as- asa asb ase asi aso asp asr ass ast at- ata atb ate ati ato atp atr ats att b-p baa bab bae bai bao bap bar bas bat bba bbb bbe bbi bbo bbp bbr bbs bbt be- bea beb bee bei beo bep ber bes bet bi- bia bib bie bii bio bip bir bis bit boa bob boe boi boo bop bor bos bot bpa bpb bpe bpi bpo bpp bpr bps bpt bra brb bre bri bro brp brr brs brt bsa bsb bse bsi bso bsp bsr bss bst bta btb bte bti bto btp btr bts btt eaa eab eae eai eao eap ear eas eat eba ebb ebe ebi ebo ebp ebr ebs ebt eea eeb eee eeo eep eer ees eet eia eib eie eii eio eip eir eis eit eo- eoa eob eoe eoi eoo eop eor eos eot ep- epa epb epe epi epo epp epr eps ept era erb ere eri ero erp err ers ert es- esa esb ese esi eso esp esr ess est eta etb ete eti eto etp etr ets ett ia- iaa iab iae iai iao iap iar ias iat iba ibb ibe ibi ibo ibp ibr ibs ibt ie- iea iee iei iep ier ies iet iia iib iie iii iio iip iir iis iit io- ioa iob ioe ioi ioo iop ior ios iot ipa ipb ipe ipi ipo ipp ipr ips ipt ir- ira irb ire iri iro irp irr irs irt is- isa isb ise isi iso isp isr iss ist ita itb ite iti ito itp its itt o-i oaa oab oae oai oao oap oar oas oat ob- oba obb obe obi obo obp obr obs obt oea oeb oee oei oeo oep oer oes oet oia oib oie oii oio oip oir ois oit oo- ooa oob ooi ooo oop oor oos oot op- opa opb ope opi opo opp opr ops opt or- ora orb ore ori oro orp orr ors ort os- osa osb ose osi oso osp osr oss ost ot- ota otb ote oti oto otp otr ots ott p-p paa pab pae pai pao pap par pas pat pba pbb pbe pbi pbo pbp pbr pbs pbt pea peb pee pei peo pep per pes pet pia pib pie pii pio pip pir pis pit poa pob poe poi poo pop por pos pot ppa ppb ppe ppi ppo ppp ppr pps ppt pra prb pre pri pro prp prr prs prt ps- psa psb pse psi pso psp psr pss pst pt- pta ptb pte pti pto ptp ptr pts ptt ra- raa rab rae rai rao rap rar ras rat rba rbb rbe rbi rbo rbp rbr rbs rbt re- rea reb ree rei reo rep rer res ret ria rib rie rii rio rip rir ris rit roa rob roe roi roo rop ror ros rot rpa rpb rpe rpi rpo rpp rpr rps rpt rra rrb rri rrp rrr rrs rrt rsa rsb rse rsi rso rsp rsr rss rst rta rtb rte rti rto rtp rtr rts rtt saa sab sae sai sao sap sar sas sat sba sbb sbe sbi sbo sbp sbr sbs sbt se- sea seb see sei seo sep ser ses set sia sib sie sii sio sip sir sis sit soa sob soe soi soo sop sor sos sot spa spb spe spi spo spp spr sps spt sr- sra srb sre sri sro srp srr srs srt ss- ssa ssb sse ssi sso ssp ssr sss sst sta stb ste sti sto stp str sts stt taa tab tae tai tao tap tar tas tat tba tbb tbe tbi tbo tbp tbr tbs tbt te- tea teb tee tei teo tep ter tes tet tia tib tie tii tio tip tir tis tit to- toa tob toe toi too top tor tos tot tpa tpb tpe tpi tpo tpp tpr tps tpt tra trb tre tri tro trp trr trs trt tsa tsb tse tsi tso tsp tsr tss tst tta ttb tte tti tto ttp ttr tts ttt