bbb bbe bbn bbo bbt bbx be- beb bee ben beo bet bex bnb bne bnn bno bnt bnx bob boe bon boo bot box btb bte btn bto btt btx bxb bxn bxo bxx ebb ebe ebn ebo ebt ebx eeb eee een eeo eet eex en- enb ene enn eno ent eo- eob eoe eon eoo eot etb ete etn eto ett etx ex- exe exo ext exx nbb nbe nbn nbo nbt nbx ne- neb nee nen neo net nex nnb nne nnn nno nnt no- nob noe non noo not nox ntb nte ntn nto ntt ntx nxt ob- obb obe obn obo obt obx oeb oee oen oeo oet oex on- onb one onn ono ont onx oo- oob oon ooo oot oox ot- otb ote otn oto ott ox- oxb oxn oxo oxt oxx t-x tbb tbe tbn tbo tbt te- teb tee ten teo tet tex tnb tne tnn tno tnt tnx to- tob toe ton too tot tox ttb tte ttn tto ttt ttx txe txn txt xbe xbx xee xen xet xex xno xon xoo xot xox xtx xxo xxx