-ic a-a a-b a-c a-i a-t aaa aab aac aag aai aao aat ab- aba abb abc abg abi abo abt ac- aca acb acc acg aci aco act ag- aga agb agc agg agi ago agt ai- aia aib aic aig aii aio ait aoa aob aoc aog aoi aoo aot at- ata atb atc atg ati ato att baa bab bac bag bai bao bat bba bbb bbc bbg bbi bbo bbt bca bcb bcc bcg bci bco bct bga bgb bgc bgg bgi bgo bgt bi- bia bib bic big bii bio bit boa bob boc bog boi boo bot bta btb btc btg bti bto btt c-- caa cab cac cag cai cao cat cba cbb cbc cbg cbi cbo cbt cca ccb ccc ccg cci cco cct cga cgb cgc cgg cgi cgo cgt ci- cia cib cic cig cii cio cit co- coa cob coc cog coi coo cot cta ctb ctc ctg cti cto ctt gaa gab gac gag gai gao gat gba gbc gbg gbi gbo gbt gca gcb gcc gcg gci gco gct gga ggb ggc ggg ggi ggo ggt gia gib gic gig gii gio git goa gob goc gog goi goo got gta gtb gtc gtg gti gto gtt ia- iaa iab iac iag iai iao iat iba ibb ibc ibg ibi ibo ibt ica icb icc icg ici ico ict iga igb igc igg igi igo igt iia iib iic iii iio iit io- ioa iob ioc iog ioi ioo iot ita itb itc itg iti ito itt o-i oaa oab oac oag oai oao oat ob- oba obb obc obg obi obo obt oc- oca ocb occ ocg oci oco oct oga ogc ogg ogi ogo ogt oia oib oic oii oio oit oo- ooa oob ooc oog ooi ooo oot ot- ota otb otc otg oti oto ott taa tab tac tag tai tao tat tba tbb tbc tbg tbi tbo tbt tca tcb tcc tcg tci tco tct tga tgb tgc tgg tgi tgo tgt tia tib tic tig tii tio tit to- toa tob toc tog toi too tot tta ttb ttc ttg tti tto ttt