bbb bbi bbn bbo bbr bi- bib bii bin bio bir bnb bni bnn bno bnr bob boi bon boo bor brb bri brn bro brr ibb ibi ibn ibo ibr iib iii iin iio iir in- inb ini inn ino inr io- iob ioi ion ioo ior ir- irb iri irn iro irr n-i nbb nbi nbn nbo nbr nib nii nin nio nir nnb nni nnn nno no- nob noi non noo nor nrb nri nrn nro nrr o-i ob- obb obi obn obo obr oib oii oin oio oir on- onb oni onn ono onr oo- oob ooi oon ooo oor or- orb ori orn oro orr rbb rbi rbn rbo rbr rib rii rin rio rir rnb rni rnn rno rnr rob roi ron roo ror rrb rri rrn rrr