bbb bbi bbn bbo bbr bbx bi- bib bii bin bio bir bix bnb bni bnn bno bnr bnx bob boi bon boo bor box brb bri brn bro brr brx bxb bxi bxn bxo bxx ibb ibi ibn ibo ibr ibx iib iii iin iio iir iix in- inb ini inn ino inr inx io- iob ioi ion ioo ior ir- irb iri irn iro irr irx ixi ixn n-i nbb nbi nbn nbo nbr nbx nib nii nin nio nir nix nnb nni nnn nno no- nob noi non noo nor nox nrb nri nrn nro nrr nrx o-i ob- obb obi obn obo obr obx oib oii oin oio oir on- onb oni onn ono onr onx oo- oob ooi oon ooo oor oox or- orb ori orn oro orr orx ox- oxb oxi oxn oxo oxx rbb rbi rbn rbo rbr rbx rib rii rin rio rir rix rnb rni rnn rno rnr rob roi ron roo ror rox rrb rri rrn rrr rxr xbr xbx xii xin xio xix xno xoi xon xoo xor xox xrx xxi xxo xxx