-er -ic a-a a-b a-c a-i a-t aaa aab aac aae aai aar aas aat ab- aba abb abc abe abi abr abs abt ac- aca acb acc ace aci acr acs act aea aeb aec aee aei aer aes aet ai- aia aib aic aie aii air ais ait ar- ara arb arc are ari arr ars art as- asa asb asc ase asi asr ass ast at- ata atb atc ate ati atr ats att baa bab bac bae bai bar bas bat bba bbb bbc bbe bbi bbr bbs bbt bca bcb bcc bce bci bcr bcs bct be- bea beb bec bee bei ber bes bet bi- bia bib bic bie bii bir bis bit bra brb bre bri brr brs brt bsa bsb bsc bse bsi bsr bss bst bta btb btc bte bti btr bts btt c-- caa cab cac cae cai car cas cat cba cbb cbc cbe cbi cbr cbs cbt cca ccb ccc cce cci ccr ccs cct ce- cea ceb cec cee cei cer ces cet ci- cia cib cic cie cii cir cis cit cra crb crc cre cri crr crs crt csa csb csc cse csi csr css cst cta ctb ctc cte cti ctr cts ctt eaa eab eac eae eai ear eas eat eba ebb ebc ebe ebi ebr ebs ebt ec- eca ecb ecc ece eci ecr ecs ect eea eeb eec eee eer ees eet eia eib eic eie eii eir eis eit era erb erc ere eri err ers ert es- esa esb esc ese esi esr ess est eta etb etc ete eti etr ets ett ia- iaa iab iac iae iai iar ias iat iba ibb ibc ibe ibi ibr ibs ibt ica icb icc ice ici icr ics ict ie- iea iec iee iei ier ies iet iia iib iic iie iii iir iis iit ir- ira irb irc ire iri irr irs irt is- isa isb isc ise isi isr iss ist ita itb itc ite iti its itt ra- raa rab rac rae rai rar ras rat rba rbb rbc rbe rbi rbr rbs rbt rca rcb rcc rce rci rcr rcs rct re- rea reb rec ree rei rer res ret ria rib ric rie rii rir ris rit rra rrb rrc rri rrr rrs rrt rsa rsb rsc rse rsi rsr rss rst rta rtb rtc rte rti rtr rts rtt saa sab sac sae sai sar sas sat sba sbb sbc sbe sbi sbr sbs sbt sca scb scc sce sci scr scs sct se- sea seb sec see sei ser ses set sia sib sic sie sii sir sis sit sr- sra srb src sre sri srr srs srt ss- ssa ssb ssc sse ssi ssr sss sst sta stb stc ste sti str sts stt taa tab tac tae tai tar tas tat tba tbb tbc tbe tbi tbr tbs tbt tca tcb tcc tce tci tcr tcs tct te- tea teb tec tee tei ter tes tet tia tib tic tie tii tir tis tit tra trb trc tre tri trr trs trt tsa tsb tsc tse tsi tsr tss tst tta ttb ttc tte tti ttr tts ttt