-ol b-p bbb bbl bbo bbp bbr blb bll blo blp blr bob bol boo bop bor bpb bpl bpo bpp bpr brb brl bro brp brr l-p lbb lbl lbo lbp lbr llb lll llo llp llr lob lol loo lop lor lpb lpl lpo lpp lpr lrb lro lrp lrr ob- obb obl obo obp obr olb oll olo olp oo- oob ool ooo oop oor op- opb opl opo opp opr or- orb orl oro orp orr p-p pbb pbl pbo pbp pbr plb pll plo plp plr pob pol poo pop por ppb ppl ppo ppp ppr prb prl pro prp prr rbb rbl rbo rbp rbr rll rlo rlp rlr rob rol roo rop ror rpb rpl rpo rpp rpr rrb rrl rrp rrr