-ic a-a a-b a-c a-i a-t aaa aab aac aae aai aan aat ab- aba abb abc abe abi abn abt ac- aca acb acc ace aci acn act aea aeb aec aee aei aen aet ai- aia aib aic aie aii ain ait an- ana anb anc ane ani ann ant at- ata atb atc ate ati atn att baa bab bac bae bai ban bat bba bbb bbc bbe bbi bbn bbt bca bcb bcc bce bci bcn bct be- bea beb bec bee bei ben bet bi- bia bib bic bie bii bin bit bna bnb bnc bne bni bnn bnt bta btb btc bte bti btn btt c-- caa cab cac cae cai can cat cba cbb cbc cbe cbi cbn cbt cca ccb ccc cce cci ccn cct ce- cea ceb cec cee cei cen cet ci- cia cib cic cie cii cin cit cn- cna cnb cnc cne cni cnn cnt cta ctb ctc cte cti ctn ctt eaa eab eac eae eai ean eat eba ebb ebc ebe ebi ebn ebt ec- eca ecb ecc ece eci ecn ect eea eeb eec eee een eet eia eib eic eie eii ein eit en- ena enb enc ene eni enn ent eta etb etc ete eti etn ett ia- iaa iab iac iae iai ian iat iba ibb ibc ibe ibi ibn ibt ica icb icc ice ici icn ict ie- iea iec iee iei ien iet iia iib iic iie iii iin iit in- ina inb inc ine ini inn int ita itb itc ite iti itn itt n-i naa nab nac nae nai nan nat nba nbb nbc nbe nbi nbn nbt nca ncb ncc nce nci ncn nct ne- nea neb nec nee nei nen net nia nib nic nie nii nin nit nna nnb nnc nne nni nnn nnt nta ntb ntc nte nti ntn ntt taa tab tac tae tai tan tat tba tbb tbc tbe tbi tbn tbt tca tcb tcc tce tci tcn tct te- tea teb tec tee tei ten tet tia tib tic tie tii tin tit tna tnb tnc tne tni tnn tnt tta ttb ttc tte tti ttn ttt