-er b-p bbb bbe bbn bbp bbr be- beb bee ben bep ber bnb bne bnn bnp bnr bpb bpe bpn bpp bpr brb bre brn brp brr ebb ebe ebn ebp ebr eeb eee een eep eer en- enb ene enn enp enr ep- epb epe epn epp epr erb ere ern erp err nbb nbe nbn nbp nbr ne- neb nee nen nep ner nnb nne nnn nnp npb npe npn npp npr nrb nre nrn nrp nrr p-p pbb pbe pbn pbp pbr peb pee pen pep per pn- pnb pne pnn pnp pnr ppb ppe ppn ppp ppr prb pre prn prp prr rbb rbe rbn rbp rbr re- reb ree ren rep rer rnb rnn rnp rnr rpb rpe rpn rpp rpr rrb rrn rrp rrr