a-a a-b a-i a-t aaa aab aai aao aat aax ab- aba abb abi abo abt abx ai- aia aib aii aio ait aix aoa aob aoi aoo aot aox at- ata atb ati ato att atx ax- axa axi axo axt axx baa bab bai bao bat bax bba bbb bbi bbo bbt bbx bi- bia bib bii bio bit bix boa bob boi boo bot box bta btb bti bto btt btx bxb bxi bxo bxx ia- iaa iab iai iao iat iba ibb ibi ibo ibt ibx iia iib iii iio iit iix io- ioa iob ioi ioo iot ita itb iti ito itt itx ixi o-i oaa oab oai oao oat oax ob- oba obb obi obo obt obx oia oib oii oio oit oo- ooa oob ooi ooo oot oox ot- ota otb oti oto ott ox- oxa oxb oxi oxo oxt oxx t-x taa tab tai tao tat tax tba tbb tbi tbo tbt tia tib tii tio tit tix to- toa tob toi too tot tox tta ttb tti tto ttt ttx txi txt xaa xat xbx xia xii xio xit xix xoa xoi xoo xot xox xti xtx xxi xxo xxx