a-a a-b a-z aaa aab aae aan aao aau aaz ab- aba abb abe abn abo abu abz aea aeb aee aen aeo aeu aez an- ana anb ane ann ano anu anz aoa aob aoe aon aoo aou au- aua aub aue aun auo auz az- aza azb aze azn azo azu azz b-u baa bab bae ban bao bau baz bba bbb bbe bbn bbo bbu be- bea beb bee ben beo beu bez bna bnb bne bnn bno bnu bnz boa bob boe bon boo bou boz bua bub bue bun buo buu buz bza bze bzn bzo bzu bzz eaa eab eae ean eao eau eaz eba ebb ebe ebn ebo ebu eea eeb eee een eeo en- ena enb ene enn eno enu enz eo- eoa eob eoe eon eoo eou eu- eua eub eue eun eze ezo ezz naa nab nae nan nao nau naz nba nbb nbe nbn nbo nbu ne- nea neb nee nen neo neu nez nna nnb nne nnn nno nnu nnz no- noa nob noe non noo nou noz nua nub nue nun nuo nuu nzb nze nzo nzz oaa oab oae oan oao oau ob- oba obb obe obn obo obu oea oeb oee oen oeo on- ona onb one onn ono onu oo- ooa oob oon ooo ou- oua oue oun ouo oza oze ozo ozu ozz ua- uaa uab uae uan uao uau uaz uba ubb ube ubn ubo ubu uea ueb uee uen un- una unb une unn uno unu uoa uob uoe uon uoo uua uue uun uuu uza uzb uzo uzu zaa zab zan zao zaz zbb zea zeb zee zen zeo zez zne znn zno zo- zoa zob zoe zon zoo zou zub zun zuz zzz