-er a-a a-b a-i aaa aab aae aaf aag aai aan aar aas ab- aba abb abe abf abg abi abn abr abs aea aeb aee aef aeg aei aen aer aes af- afa afb afe aff afg afi afn afr afs ag- aga agb age agf agg agi agn agr ags ai- aia aib aie aif aig aii ain air ais an- ana anb ane anf ang ani ann anr ans ar- ara arb are arf arg ari arn arr ars as- asa asb ase asf asg asi asn asr ass baa bab bae baf bag bai ban bar bas bba bbb bbe bbf bbg bbi bbn bbr bbs be- bea beb bee bef beg bei ben ber bes bfa bfb bfe bff bfg bfi bfn bfr bfs bga bgb bge bgf bgg bgi bgn bgr bgs bi- bia bib bie bif big bii bin bir bis bna bnb bne bnf bng bni bnn bnr bns bra brb bre brf brg bri brn brr brs bsa bsb bse bsf bsg bsi bsn bsr bss eaa eab eae eaf eag eai ean ear eas eba ebb ebe ebf ebg ebi ebn ebr ebs eea eeb eee eef eeg een eer ees ef- efa efb efe eff efg efi efr efs ega egb ege egf egg egi egn egr egs eia eib eie eif eig eii ein eir eis en- ena enb ene enf eng eni enn enr ens era erb ere erf erg eri ern err ers es- esa esb ese esf esg esi esn esr ess faa fab fae faf fag fai fan far fas fba fbb fbe fbf fbg fbi fbn fbr fbs fea feb fee fef feg fei fen fer fes ffa ffe fff ffg ffi ffn ffr ffs fga fgb fge fgf fgg fgi fgn fgr fgs fia fib fie fif fig fii fin fir fis fna fnb fne fnf fng fni fnn fnr fns fra frb fre frf frg fri frn frr frs fsa fsb fse fsf fsg fsi fsn fsr fss gaa gab gae gaf gag gai gan gar gas gba gbe gbf gbg gbi gbn gbr gbs ge- gea geb gee gef geg gei gen ger ges gfa gfb gfe gff gfi gfr gfs gga ggb ggg ggi ggn ggr ggs gia gib gie gif gig gii gin gir gis gna gnb gne gnf gni gnn gnr gns gra grb gre grf grg gri grn grr grs gsa gsb gse gsf gsg gsi gsn gsr gss i-f ia- iaa iab iae iaf iag iai ian iar ias iba ibb ibe ibf ibg ibi ibn ibr ibs ie- iea iee ief ieg iei ien ier ies ifa ifb ife iff ifg ifi ifn ifr ifs iga igb ige igf igg igi ign igr igs iia iib iie iif iii iin iir iis in- ina inb ine inf ing ini inn inr ins ir- ira irb ire irf irg iri irn irr irs is- isa isb ise isf isg isi isn isr iss n-i naa nab nae naf nag nai nan nar nas nba nbb nbe nbf nbg nbi nbn nbr nbs ne- nea neb nee nef neg nei nen ner nes nfa nfb nfe nff nfi nfn nfr nfs nga ngb nge ngf ngg ngi ngn ngs nia nib nie nif nig nii nin nir nis nna nnb nne nnf nng nni nnn nns nra nrb nre nrf nrg nri nrn nrr nrs nsa nsb nse nsf nsg nsi nsn nsr nss ra- raa rab rae raf rag rai ran rar ras rba rbb rbe rbf rbg rbi rbn rbr rbs re- rea reb ree ref reg rei ren rer res rfa rfb rfe rff rfg rfi rfn rfr rfs rga rgb rge rgf rgg rgi rgn rgr rgs ria rib rie rif rig rii rin rir ris rna rnb rng rni rnn rnr rns rra rrb rrf rrg rri rrn rrr rrs rsa rsb rse rsf rsg rsi rsn rsr rss saa sab sae saf sag sai san sar sas sba sbb sbe sbf sbg sbi sbn sbr sbs se- sea seb see sef seg sei sen ser ses sfa sfb sfe sff sfg sfi sfn sfr sfs sga sgb sge sgf sgg sgi sgn sgr sgs sia sib sie sif sig sii sin sir sis sna snb sne snf sng sni snn snr sns sr- sra srb sre srf srg sri srn srr srs ss- ssa ssb sse ssf ssg ssi ssn ssr sss