-ic a-a a-b a-c a-i aaa aab aac aad aai aan ab- aba abb abc abd abi abn ac- aca acb acc acd aci acn ad- ada adb adc add adi adn ai- aia aib aic aid aii ain an- ana anb anc and ani ann baa bab bac bad bai ban bba bbb bbc bbd bbi bbn bca bcb bcc bcd bci bcn bda bdb bdc bdd bdi bi- bia bib bic bid bii bin bna bnb bnc bnd bni bnn c-- caa cab cac cad cai can cba cbb cbc cbd cbi cbn cca ccb ccc ccd cci ccn cda cdb cdc cdd cdi cdn ci- cia cib cic cid cii cin cn- cna cnb cnc cnd cni cnn daa dab dac dad dai dan dba dbb dbc dbd dbi dbn dca dcb dcc dcd dci dcn dda ddb ddc ddd ddi ddn di- dia dib dic did dii din dna dnb dnc dnd dni dnn i-d ia- iaa iab iac iad iai ian iba ibb ibc ibd ibi ibn ica icb icc icd ici icn ida idb idc idd idi idn iia iib iic iid iii iin in- ina inb inc ind ini inn n-i naa nab nac nad nai nan nba nbb nbc nbd nbi nbn nca ncb ncc ncd nci ncn nda ndb ndc ndd ndi ndn nia nib nic nid nii nin nna nnb nnc nni nnn