a-a a-b a-i a-t a-z aaa aab aai aao aar aat aaz ab- aba abb abi abo abr abt abz ai- aia aib aii aio air ait aiz aoa aob aoi aoo aor aot ar- ara arb ari aro arr art arz at- ata atb ati ato atr att atz az- aza azb azi azo azt azz baa bab bai bao bar bat baz bba bbb bbi bbo bbr bbt bi- bia bib bii bio bir bit biz boa bob boi boo bor bot boz bra brb bri bro brr brt brz bta btb bti bto btr btt btz bza bzo bzr bzz ia- iaa iab iai iao iar iat iaz iba ibb ibi ibo ibr ibt ibz iia iib iii iio iir iit io- ioa iob ioi ioo ior iot ir- ira irb iri iro irr irt ita itb iti ito itt itz iza izi izo izz o-i oaa oab oai oao oar oat ob- oba obb obi obo obr obt oia oib oii oio oir oit oiz oo- ooa oob ooi ooo oor oot or- ora orb ori oro orr ort orz ot- ota otb oti oto otr ott otz oza ozo ozt ozz ra- raa rab rai rao rar rat raz rba rbb rbi rbo rbr rbt ria rib rii rio rir rit riz roa rob roi roo ror rot roz rra rrb rri rrr rrt rta rtb rti rto rtr rtt rtz rza rzb rzo taa tab tai tao tar tat taz tba tbb tbi tbo tbr tbt tbz tia tib tii tio tir tit tiz to- toa tob toi too tor tot toz tra trb tri tro trr trt trz tta ttb tti tto ttr ttt tza zaa zab zai zao zar zat zaz zbb zbr zbt zia zib zio zir zit ziz zo- zoa zob zoi zoo zor zot zro zta ztr zzr zzt zzz