-ic a-a a-b a-c a-i aaa aab aac aai aan ab- aba abb abc abi abn ac- aca acb acc aci acn ai- aia aib aic aii ain an- ana anb anc ani ann baa bab bac bai ban bba bbb bbc bbi bbn bca bcb bcc bci bcn bi- bia bib bic bii bin bna bnb bnc bni bnn c-- caa cab cac cai can cba cbb cbc cbi cbn cca ccb ccc cci ccn ci- cia cib cic cii cin cn- cna cnb cnc cni cnn ia- iaa iab iac iai ian iba ibb ibc ibi ibn ica icb icc ici icn iia iib iic iii iin in- ina inb inc ini inn n-i naa nab nac nai nan nba nbb nbc nbi nbn nca ncb ncc nci ncn nia nib nic nii nin nna nnb nnc nni nnn