-er a-a a-c aaa aac aae aak aan aap aar aas ac- aca acc ace ack acn acp acr acs aea aec aee aek aen aep aer aes aka akc ake akk akn akp akr aks an- ana anc ane ank ann anp anr ans ap- apa apc ape apk apn app apr aps ar- ara arc are ark arn arp arr ars as- asa asc ase ask asn asp asr ass c-- caa cac cae cak can cap car cas cca ccc cce cck ccn ccp ccr ccs ce- cea cec cee cek cen cep cer ces cka ckc cks cn- cna cnc cne cnn cnp cnr cns cpa cpc cpe cpk cpn cpp cpr cps cra crc cre crk crn crp crr crs csa csc cse csk csn csp csr css eaa eac eae eak ean eap ear eas ec- eca ecc ece eck ecn ecr ecs eea eec eee eek een eep eer ees eka ekc eke ekp ekr eks en- ena enc ene enk enn enp enr ens ep- epa epc epe epn epp epr eps era erc ere erk ern erp err ers es- esa esc ese esk esn esp esr ess ka- kaa kac kae kak kan kap kar kas kca kcc kce kck kcn kcp kcr kcs ke- kea kec kee kek ken kep ker kes kkc kke kkk kkn kkp kkr kks kn- kna knc kne knk knn knp knr kpa kpc kpe kpk kpn kpp kpr kps kra krc krk krn krp krr krs ksa ksc kse ksk ksn ksp ksr kss naa nac nae nak nan nap nar nas nca ncc nce nck ncn ncp ncr ncs ne- nea nec nee nek nen nep ner nes nka nkc nke nkk nkn nkp nkr nks nna nnc nne nnk nnn nnp nns npa npc npe npn npp npr nps nra nrc nre nrk nrn nrp nrr nrs nsa nsc nse nsk nsn nsp nsr nss p-p paa pac pae pak pan pap par pas pca pcc pce pck pcn pcp pcr pcs pea pec pee pek pen pep per pes pka pkc pke pkn pkp pkr pks pn- pna pnc pne pnk pnn pnp pnr pns ppa ppc ppe ppk ppn ppp ppr pps pra prc pre prk prn prp prr prs ps- psa psc pse psk psn psp psr pss ra- raa rac rae rak ran rap rar ras rca rcc rce rcn rcp rcr rcs re- rea rec ree rek ren rep rer res rkc rke rkk rkp rks rna rnc rnn rnp rnr rns rpa rpc rpe rpk rpn rpp rpr rps rra rrc rrk rrn rrp rrr rrs rsa rsc rse rsk rsn rsp rsr rss saa sac sae sak san sap sar sas sca scc sce sck scn scp scr scs se- sea sec see sek sen sep ser ses sk- ska skc ske skk skp skr sks sna snc sne snk snn snp snr sns spa spc spe spk spn spp spr sps sr- sra src sre srk srn srp srr srs ss- ssa ssc sse ssk ssn ssp ssr sss