-ic a-a a-b a-c a-i aaa aab aac aag aai aao ab- aba abb abc abg abi abo ac- aca acb acc acg aci aco ag- aga agb agc agg agi ago ai- aia aib aic aig aii aio aoa aob aoc aog aoi aoo baa bab bac bag bai bao bba bbb bbc bbg bbi bbo bca bcb bcc bcg bci bco bga bgb bgc bgg bgi bgo bi- bia bib bic big bii bio boa bob boc bog boi boo c-- caa cab cac cag cai cao cba cbb cbc cbg cbi cbo cca ccb ccc ccg cci cco cga cgb cgc cgg cgi cgo ci- cia cib cic cig cii cio co- coa cob coc cog coi coo gaa gab gac gag gai gao gba gbc gbg gbi gbo gca gcb gcc gcg gci gco gga ggb ggc ggg ggi ggo gia gib gic gig gii gio goa gob goc gog goi goo ia- iaa iab iac iag iai iao iba ibb ibc ibg ibi ibo ica icb icc icg ici ico iga igb igc igg igi igo iia iib iic iii iio io- ioa iob ioc iog ioi ioo o-i oaa oab oac oag oai oao ob- oba obb obc obg obi obo oc- oca ocb occ ocg oci oco oga ogc ogg ogi ogo oia oib oic oii oio oo- ooa oob ooc oog ooi ooo