-er b-u bbb bbe bbm bbn bbr bbu be- beb bee bem ben ber beu bmb bme bmm bmn bmr bmu bnb bne bnn bnr bnu brb bre brm brn brr bru bub bue bum bun bur buu ebb ebe ebm ebn ebr ebu eeb eee eem een eer em- emb eme emm emn emr emu en- enb ene enm enn enr enu erb ere erm ern err eru eu- eub eue eun eur m-r mbb mbe mbm mbr mbu meb mee mem men mer meu mmb mme mmm mmn mmr mmu mnb mne mnm mnn mnr mnu mrb mre mrm mrn mrr mru mub mue mum mun mur muu nbb nbe nbm nbn nbr nbu ne- neb nee nem nen ner neu nmb nme nmm nmn nmr nmu nnb nne nnm nnn nnu nrb nre nrm nrn nrr nru nub nue num nun nur nuu rbb rbe rbm rbn rbr rbu re- reb ree rem ren rer reu rmb rme rmm rmn rmr rnb rnm rnn rnr rnu rrb rrm rrn rrr rru rub rue rum run rur ruu ubb ube ubn ubr ubu ueb uee uem uen uer um- umb ume umm umn umr umu un- unb une unm unn unr unu ur- urb ure urm urn urr uru uue uum uun uur uuu