-ol b-u bbb bbl bbn bbo bbr bbu blb bll bln blo blr blu bnb bnl bnn bno bnr bnu bob bol bon boo bor bou brb brl brn bro brr bru bub bul bun buo bur buu lbb lbl lbo lbr lbu llb lll lln llo llr llu lnb lnl lnn lno lnr lnu lob lol lon loo lor lou lrb lrn lro lrr lru lub lul lun luo lur luu nbb nbl nbn nbo nbr nbu nlb nll nln nlo nlr nlu nnb nnl nnn nno nnu no- nob nol non noo nor nou nrb nrl nrn nro nrr nru nub nul nun nuo nur nuu ob- obb obl obn obo obr obu olb oll oln olo olu on- onb onl onn ono onr onu oo- oob ool oon ooo oor or- orb orl orn oro orr oru ou- oul oun ouo our rbb rbl rbn rbo rbr rbu rll rln rlo rlr rlu rnb rnn rno rnr rnu rob rol ron roo ror rou rrb rrl rrn rrr rru rub run ruo rur ruu ubb ubl ubn ubo ubr ubu ulb ull uln ulo ulr ulu un- unb unl unn uno unr unu uob uol uon uoo uor ur- urb url urn uro urr uru uun uur uuu