a-a a-b aaa aab aae aag aak aan aas ab- aba abb abe abg abk abn abs aea aeb aee aeg aek aen aes ag- aga agb age agg agk agn ags aka akb ake akg akk akn aks an- ana anb ane ang ank ann ans as- asa asb ase asg ask asn ass baa bab bae bag bak ban bas bba bbb bbe bbg bbk bbn bbs be- bea beb bee beg bek ben bes bga bgb bge bgg bgk bgn bgs bka bkb bke bkg bkk bkn bks bna bnb bne bng bnk bnn bns bsa bsb bse bsg bsk bsn bss eaa eab eae eag eak ean eas eba ebb ebe ebg ebk ebn ebs eea eeb eee eeg eek een ees ega egb ege egg egn egs eka ekb eke ekg eks en- ena enb ene eng enk enn ens es- esa esb ese esg esk esn ess gaa gab gae gag gak gan gas gba gbe gbg gbk gbn gbs ge- gea geb gee geg gek gen ges gga ggb ggg ggn ggs gka gkb gkn gks gna gnb gne gnn gns gsa gsb gse gsg gsk gsn gss ka- kaa kab kae kag kak kan kas kba kbb kbe kbk kbn kbs ke- kea keb kee keg kek ken kes kga kgb kgs kkb kke kkk kkn kks kn- kna kne kng knk knn ksa ksb kse ksg ksk ksn kss naa nab nae nag nak nan nas nba nbb nbe nbg nbk nbn nbs ne- nea neb nee neg nek nen nes nga ngb nge ngg ngk ngn ngs nka nke nkk nkn nks nna nnb nne nng nnk nnn nns nsa nsb nse nsg nsk nsn nss saa sab sae sag sak san sas sba sbb sbe sbg sbk sbn sbs se- sea seb see seg sek sen ses sga sgb sge sgg sgk sgn sgs sk- ska skb ske skg skk sks sna snb sne sng snk snn sns ss- ssa ssb sse ssg ssk ssn sss