-er a-a a-c aaa aac aad aae aak aap aar aas ac- aca acc acd ace ack acp acr acs ad- ada adc add ade adk adp adr ads aea aec aed aee aek aep aer aes aka akc akd ake akk akp akr aks ap- apa apc apd ape apk app apr aps ar- ara arc ard are ark arp arr ars as- asa asc asd ase ask asp asr ass c-- caa cac cad cae cak cap car cas cca ccc ccd cce cck ccp ccr ccs cda cdc cdd cde cdk cdp cdr cds ce- cea cec ced cee cek cep cer ces cka ckc ckd cks cpa cpc cpd cpe cpk cpp cpr cps cra crc crd cre crk crp crr crs csa csc csd cse csk csp csr css daa dac dad dae dak dap dar das dca dcc dcd dce dck dcp dcr dcs dda ddc ddd dde ddk ddp ddr dds de- dea dec ded dee dek dep der des dka dkc dke dkk dkp dkr dks dpa dpc dpd dpe dpk dpp dpr dps dra drc drd dre drk drp drr drs dsa dsc dsd dse dsk dsp dsr dss eaa eac ead eae eak eap ear eas ec- eca ecc ecd ece eck ecr ecs ed- eda edc edd ede edk edp edr eds eea eec eed eee eek eep eer ees eka ekc ekd eke ekp ekr eks ep- epa epc epd epe epp epr eps era erc erd ere erk erp err ers es- esa esc esd ese esk esp esr ess ka- kaa kac kad kae kak kap kar kas kca kcc kcd kce kck kcp kcr kcs kda kdc kde kdk kdp kdr kds ke- kea kec ked kee kek kep ker kes kkc kke kkk kkp kkr kks kpa kpc kpd kpe kpk kpp kpr kps kra krc krd krk krp krr krs ksa ksc ksd kse ksk ksp ksr kss p-p paa pac pad pae pak pap par pas pca pcc pcd pce pck pcp pcr pcs pda pdc pdd pde pdk pdp pdr pds pea pec ped pee pek pep per pes pka pkc pkd pke pkp pkr pks ppa ppc ppd ppe ppk ppp ppr pps pra prc prd pre prk prp prr prs ps- psa psc psd pse psk psp psr pss ra- raa rac rad rae rak rap rar ras rca rcc rcd rce rcp rcr rcs rda rdc rdd rde rdp rdr rds re- rea rec red ree rek rep rer res rkc rke rkk rkp rks rpa rpc rpd rpe rpk rpp rpr rps rra rrc rrd rrk rrp rrr rrs rsa rsc rsd rse rsk rsp rsr rss saa sac sad sae sak sap sar sas sca scc scd sce sck scp scr scs sda sdc sdd sde sdk sdp sdr sds se- sea sec sed see sek sep ser ses sk- ska skc skd ske skk skp skr sks spa spc spd spe spk spp spr sps sr- sra src srd sre srk srp srr srs ss- ssa ssc ssd sse ssk ssp ssr sss