bbb bbg bbo bbr bgb bgg bgo bgr bgv bob bog boo bor bov brb brg bro brr brv bvb bvg bvo bvr bvv gbg gbo gbr gbv ggb ggg ggo ggr ggv gob gog goo gor gov grb grg gro grr grv gvb gvg gvo gvr ob- obb obg obo obr obv ogg ogo oo- oob oog ooo oor oov or- orb org oro orr orv ov- ovb ovo ovv rbb rbg rbo rbr rgb rgg rgo rgr rgv rob rog roo ror rov rrb rrg rrr rvb rvg rvo rvr rvv vbg vbo vbr vbv vgg vgo vgr vob vog voo vor vov vrb vrg vrr vvb vvg vvo vvr vvv