bbb bbi bbn bbo bi- bib bii bin bio biz bnb bni bnn bno bnz bob boi bon boo boz bzn bzo bzz ibb ibi ibn ibo ibz iib iii iin iio in- inb ini inn ino io- iob ioi ion ioo izi izo izz n-i nbb nbi nbn nbo nib nii nin nio niz nnb nni nnn nno nnz no- nob noi non noo noz nzb nzi nzo nzz o-i ob- obb obi obn obo oib oii oin oio oiz on- onb oni onn ono oo- oob ooi oon ooo ozo ozz zbb zib zin zio ziz znn zno zo- zob zoi zon zoo zzz