a-a a-b a-t aaa aab aae aam aan aao aas aat ab- aba abb abe abm abn abo abs abt aea aeb aee aem aen aeo aes aet ama amb ame amm amn amo ams amt an- ana anb ane anm ann ano ans ant aoa aob aoe aom aon aoo aos aot as- asa asb ase asm asn aso ass ast at- ata atb ate atm atn ato ats att baa bab bae bam ban bao bas bat bba bbb bbe bbm bbn bbo bbs bbt be- bea beb bee bem ben beo bes bet bma bmb bme bmm bmn bmo bms bmt bna bnb bne bnn bno bns bnt boa bob boe bom bon boo bos bot bsa bsb bse bsm bsn bso bss bst bta btb bte btm btn bto bts btt eaa eab eae eam ean eao eas eat eba ebb ebe ebm ebn ebo ebs ebt eea eeb eee eem een eeo ees eet em- ema emb eme emm emn emo ems emt en- ena enb ene enm enn eno ens ent eo- eoa eob eoe eom eon eoo eos eot es- esa esb ese esm esn eso ess est eta etb ete etm etn eto ets ett m-o maa mab mae mam man mao mas mat mba mbb mbe mbm mbo mbs mbt mea meb mee mem men meo mes met mma mmb mme mmm mmn mmo mms mmt mna mnb mne mnm mnn mno mns mnt moa mob moe mom mon moo mos mot msa msb mse msm msn mso mss mst mta mtb mte mtm mtn mto mts mtt naa nab nae nam nan nao nas nat nba nbb nbe nbm nbn nbo nbs nbt ne- nea neb nee nem nen neo nes net nma nmb nme nmm nmn nmo nms nmt nna nnb nne nnm nnn nno nns nnt no- noa nob noe nom non noo nos not nsa nsb nse nsm nsn nso nss nst nta ntb nte ntm ntn nto nts ntt oaa oab oae oam oan oao oas oat ob- oba obb obe obm obn obo obs obt oea oeb oee oem oen oeo oes oet om- oma omb ome omm omn omo oms omt on- ona onb one onn ono ons ont oo- ooa oob oom oon ooo oos oot os- osa osb ose osm osn oso oss ost ot- ota otb ote otm otn oto ots ott saa sab sae sam san sao sas sat sba sbb sbe sbm sbn sbo sbs sbt se- sea seb see sem sen seo ses set sma smb sme smm smn smo sms smt sna snb sne snm snn sno sns snt soa sob soe som son soo sos sot ss- ssa ssb sse ssm ssn sso sss sst sta stb ste stm stn sto sts stt taa tab tae tam tan tao tas tat tba tbb tbe tbm tbn tbo tbs tbt te- tea teb tee tem ten teo tes tet tma tmb tme tmm tmn tmo tms tmt tna tnb tne tnm tnn tno tns tnt to- toa tob toe tom ton too tos tot tsa tsb tse tsm tsn tso tss tst tta ttb tte ttm ttn tto tts ttt