-ol bbb bbk bbl bbn bbo bbt bkb bkk bkl bkn bko bkt blb blk bll bln blo blt bnb bnk bnl bnn bno bnt bob bok bol bon boo bot btb btk btl btn bto btt k-t kbb kbk kbl kbn kbo kkb kkk kkl kkn kkt kl- klb klo klt kn- knk knl knn kno knt kob kok kol kon koo kot ktb ktk ktl ktn kto ktt lbb lbk lbl lbo lbt lkb lkl lkt llb llk lll lln llo llt lnb lnk lnl lnn lno lnt lob lok lol lon loo lot ltb ltk ltl lto ltt nbb nbk nbl nbn nbo nbt nkk nkn nko nkt nlb nlk nll nln nlo nlt nnb nnk nnl nnn nno nnt no- nob nok nol non noo not ntb ntk ntn nto ntt ob- obb obk obl obn obo obt okb okk okl oko olb olk oll oln olo olt on- onb onk onl onn ono ont oo- oob ook ool oon ooo oot ot- otb otk otl otn oto ott tbb tbk tbl tbn tbo tbt tkb tkk tkl tko tkt tlk tll tln tlo tlt tnb tnk tnl tnn tno tnt to- tob tok tol ton too tot ttb ttk ttl ttn tto ttt