-er a-a a-c aaa aac aae aaf aag aan aar aas ac- aca acc ace acf acg acn acr acs aea aec aee aef aeg aen aer aes af- afa afc afe aff afg afn afr afs ag- aga agc age agf agg agn agr ags an- ana anc ane anf ang ann anr ans ar- ara arc are arf arg arn arr ars as- asa asc ase asf asg asn asr ass c-- caa cac cae caf cag can car cas cca ccc cce ccf ccg ccn ccr ccs ce- cea cec cee cef ceg cen cer ces cfa cfc cfe cff cfg cfn cfr cfs cga cgc cge cgg cgn cgr cgs cn- cna cnc cne cnf cng cnn cnr cns cra crc cre crf crg crn crr crs csa csc cse csf csg csn csr css eaa eac eae eaf eag ean ear eas ec- eca ecc ece ecf ecg ecn ecr ecs eea eec eee eef eeg een eer ees ef- efa efc efe eff efg efr efs ega egc ege egf egg egn egr egs en- ena enc ene enf eng enn enr ens era erc ere erf erg ern err ers es- esa esc ese esf esg esn esr ess faa fac fae faf fag fan far fas fca fcc fce fcf fcg fcn fcr fcs fea fec fee fef feg fen fer fes ffa ffc ffe fff ffg ffn ffr ffs fga fgc fge fgf fgg fgn fgr fgs fna fnc fne fnf fng fnn fnr fns fra frc fre frf frg frn frr frs fsa fsc fse fsf fsg fsn fsr fss gaa gac gae gaf gag gan gar gas gca gcc gce gcf gcg gcn gcr gcs ge- gea gec gee gef geg gen ger ges gfa gfc gfe gff gfr gfs gga ggc ggg ggn ggr ggs gna gnc gne gnf gnn gnr gns gra grc gre grf grg grn grr grs gsa gsc gse gsf gsg gsn gsr gss naa nac nae naf nag nan nar nas nca ncc nce ncf ncg ncn ncr ncs ne- nea nec nee nef neg nen ner nes nfa nfc nfe nff nfn nfr nfs nga ngc nge ngf ngg ngn ngs nna nnc nne nnf nng nnn nns nra nrc nre nrf nrg nrn nrr nrs nsa nsc nse nsf nsg nsn nsr nss ra- raa rac rae raf rag ran rar ras rca rcc rce rcf rcg rcn rcr rcs re- rea rec ree ref reg ren rer res rfa rfc rfe rff rfg rfn rfr rfs rga rgc rge rgf rgg rgn rgr rgs rna rnc rng rnn rnr rns rra rrc rrf rrg rrn rrr rrs rsa rsc rse rsf rsg rsn rsr rss saa sac sae saf sag san sar sas sca scc sce scf scg scn scr scs se- sea sec see sef seg sen ser ses sfa sfc sfe sff sfg sfn sfr sfs sga sgc sge sgf sgg sgn sgr sgs sna snc sne snf sng snn snr sns sr- sra src sre srf srg srn srr srs ss- ssa ssc sse ssf ssg ssn ssr sss