-er a-a a-c aaa aac aae aaf aan aao aar aas ac- aca acc ace acf acn aco acr acs aea aec aee aef aen aeo aer aes af- afa afc afe aff afn afo afr afs an- ana anc ane anf ann ano anr ans aoa aoc aoe aof aon aoo aor aos ar- ara arc are arf arn aro arr ars as- asa asc ase asf asn aso asr ass c-- caa cac cae caf can cao car cas cca ccc cce ccf ccn cco ccr ccs ce- cea cec cee cef cen ceo cer ces cfa cfc cfe cff cfn cfo cfr cfs cn- cna cnc cne cnf cnn cno cnr cns co- coa coc coe cof con coo cor cos cra crc cre crf crn cro crr crs csa csc cse csf csn cso csr css eaa eac eae eaf ean eao ear eas ec- eca ecc ece ecf ecn eco ecr ecs eea eec eee eef een eeo eer ees ef- efa efc efe eff efo efr efs en- ena enc ene enf enn eno enr ens eo- eoa eoc eoe eof eon eoo eor eos era erc ere erf ern ero err ers es- esa esc ese esf esn eso esr ess faa fac fae faf fan fao far fas fca fcc fce fcf fcn fco fcr fcs fea fec fee fef fen feo fer fes ffa ffc ffe fff ffn ffo ffr ffs fna fnc fne fnf fnn fnr fns foa foc foe fof fon foo for fos fra frc fre frf frn fro frr frs fsa fsc fse fsf fsn fso fsr fss naa nac nae naf nan nao nar nas nca ncc nce ncf ncn nco ncr ncs ne- nea nec nee nef nen neo ner nes nfa nfc nfe nff nfn nfo nfr nfs nna nnc nne nnf nnn nno nns no- noa noc noe nof non noo nor nos nra nrc nre nrf nrn nro nrr nrs nsa nsc nse nsf nsn nso nsr nss oaa oac oae oaf oan oao oar oas oc- oca occ ocf ocn oco ocr ocs oea oec oee oef oen oeo oer oes of- ofa ofc ofe off ofn ofo ofr ofs on- ona onc one onf onn ono onr ons oo- ooa ooc oof oon ooo oor oos or- ora orc ore orf orn oro orr ors os- osa osc ose osf osn oso osr oss ra- raa rac rae raf ran rao rar ras rca rcc rce rcf rcn rco rcr rcs re- rea rec ree ref ren reo rer res rfa rfc rfe rff rfn rfo rfr rfs rna rnc rnn rno rnr rns roa roc roe rof ron roo ror ros rra rrc rrf rrn rrr rrs rsa rsc rse rsf rsn rso rsr rss saa sac sae saf san sao sar sas sca scc sce scf scn sco scr scs se- sea sec see sef sen seo ser ses sfa sfc sfe sff sfn sfo sfr sfs sna snc sne snf snn sno snr sns soa soc soe sof son soo sor sos sr- sra src sre srf srn sro srr srs ss- ssa ssc sse ssf ssn sso ssr sss