a-a a-b aaa aab aae aag aak aan aao aas ab- aba abb abe abg abk abn abo abs aea aeb aee aeg aek aen aeo aes ag- aga agb age agg agk agn ago ags aka akb ake akg akk akn ako aks an- ana anb ane ang ank ann ano ans aoa aob aoe aog aok aon aoo aos as- asa asb ase asg ask asn aso ass baa bab bae bag bak ban bao bas bba bbb bbe bbg bbk bbn bbo bbs be- bea beb bee beg bek ben beo bes bga bgb bge bgg bgk bgn bgo bgs bka bkb bke bkg bkk bkn bko bks bna bnb bne bng bnk bnn bno bns boa bob boe bog bok bon boo bos bsa bsb bse bsg bsk bsn bso bss eaa eab eae eag eak ean eao eas eba ebb ebe ebg ebk ebn ebo ebs eea eeb eee eeg eek een eeo ees ega egb ege egg egn ego egs eka ekb eke ekg eko eks en- ena enb ene eng enk enn eno ens eo- eoa eob eoe eog eok eon eoo eos es- esa esb ese esg esk esn eso ess gaa gab gae gag gak gan gao gas gba gbe gbg gbk gbn gbo gbs ge- gea geb gee geg gek gen geo ges gga ggb ggg ggn ggo ggs gka gkb gkn gko gks gna gnb gne gnn gno gns goa gob goe gog gok gon goo gos gsa gsb gse gsg gsk gsn gso gss ka- kaa kab kae kag kak kan kao kas kba kbb kbe kbk kbn kbo kbs ke- kea keb kee keg kek ken keo kes kga kgb kgo kgs kkb kke kkk kkn kks kn- kna kne kng knk knn kno koa kob koe kog kok kon koo kos ksa ksb kse ksg ksk ksn kso kss naa nab nae nag nak nan nao nas nba nbb nbe nbg nbk nbn nbo nbs ne- nea neb nee neg nek nen neo nes nga ngb nge ngg ngk ngn ngo ngs nka nke nkk nkn nko nks nna nnb nne nng nnk nnn nno nns no- noa nob noe nog nok non noo nos nsa nsb nse nsg nsk nsn nso nss oaa oab oae oag oak oan oao oas ob- oba obb obe obg obk obn obo obs oea oeb oee oeg oen oeo oes oga oge ogg ogn ogo ogs oka okb oke okg okk oko oks on- ona onb one ong onk onn ono ons oo- ooa oob oog ook oon ooo oos os- osa osb ose osg osk osn oso oss saa sab sae sag sak san sao sas sba sbb sbe sbg sbk sbn sbo sbs se- sea seb see seg sek sen seo ses sga sgb sge sgg sgk sgn sgo sgs sk- ska skb ske skg skk sko sks sna snb sne sng snk snn sno sns soa sob soe sog sok son soo sos ss- ssa ssb sse ssg ssk ssn sso sss