-er a-a a-b a-t aaa aab aad aae aak aan aar aat ab- aba abb abd abe abk abn abr abt ad- ada adb add ade adk adn adr adt aea aeb aed aee aek aen aer aet aka akb akd ake akk akn akr an- ana anb and ane ank ann anr ant ar- ara arb ard are ark arn arr art at- ata atb atd ate atn atr att baa bab bad bae bak ban bar bat bba bbb bbd bbe bbk bbn bbr bbt bda bdb bdd bde bdk bdr bdt be- bea beb bed bee bek ben ber bet bka bkb bke bkk bkn bkr bkt bna bnb bnd bne bnk bnn bnr bnt bra brb brd bre brk brn brr brt bta btb btd bte btk btn btr btt daa dab dad dae dak dan dar dat dba dbb dbd dbe dbk dbn dbr dbt dda ddb ddd dde ddk ddn ddr ddt de- dea deb ded dee dek den der det dka dkb dke dkk dkr dkt dna dnb dnd dne dnk dnn dnr dnt dra drb drd dre drk drn drr drt dta dtb dtd dte dtk dtn dtr dtt eaa eab ead eae eak ean ear eat eba ebb ebd ebe ebk ebn ebr ebt ed- eda edb edd ede edk edn edr edt eea eeb eed eee eek een eer eet eka ekb ekd eke ekr ekt en- ena enb end ene enk enn enr ent era erb erd ere erk ern err ert eta etb etd ete etk etn etr ett k-t ka- kaa kab kad kae kak kan kar kat kba kbb kbd kbe kbk kbn kbr kda kdb kde kdk kdr kdt ke- kea keb ked kee kek ken ker ket kkb kke kkk kkn kkr kkt kn- kna knd kne knk knn knr knt kra krd krk krn krr krt kta ktb kte ktk ktn ktr ktt naa nab nad nae nak nan nar nat nba nbb nbd nbe nbk nbn nbr nbt nda ndb ndd nde ndk ndn ndr ndt ne- nea neb ned nee nek nen ner net nka nke nkk nkn nkr nkt nna nnb nne nnk nnn nnt nra nrb nrd nre nrk nrn nrr nrt nta ntb ntd nte ntk ntn ntr ntt ra- raa rab rad rae rak ran rar rat rba rbb rbd rbe rbk rbn rbr rbt rda rdb rdd rde rdn rdr rdt re- rea reb red ree rek ren rer ret rkb rke rkk rkt rna rnb rnd rnn rnr rnt rra rrb rrd rrk rrn rrr rrt rta rtb rtd rte rtk rtn rtr rtt taa tab tad tae tak tan tar tat tba tbb tbd tbe tbk tbn tbr tbt tda tdb tdd tde tdk tdn tdr tdt te- tea teb ted tee tek ten ter tet tka tkb tke tkk tkr tkt tna tnb tnd tne tnk tnn tnr tnt tra trb trd tre trk trn trr trt tta ttb ttd tte ttk ttn ttr ttt