-ol bbb bbl bbn bbo bbr blb bll bln blo blr blz bnb bnl bnn bno bnr bnz bob bol bon boo bor boz brb brl brn bro brr brz bzn bzo bzr bzz lbb lbl lbo lbr llb lll lln llo llr llz lnb lnl lnn lno lnr lob lol lon loo lor loz lrb lrn lro lrr lrz lzo lzr nbb nbl nbn nbo nbr nlb nll nln nlo nlr nlz nnb nnl nnn nno nnz no- nob nol non noo nor noz nrb nrl nrn nro nrr nrz nzb nzo nzz ob- obb obl obn obo obr olb oll oln olo on- onb onl onn ono onr oo- oob ool oon ooo oor or- orb orl orn oro orr orz ozo ozz rbb rbl rbn rbo rbr rll rln rlo rlr rnb rnn rno rnr rnz rob rol ron roo ror roz rrb rrl rrn rrr rzb rzo zbb zbl zbr zlr znn zno zo- zob zol zon zoo zor zrl zro zzr zzz