-er -ic a-a a-c a-i a-t aaa aac aae aag aai aao aar aat aax ac- aca acc ace acg aci aco acr act acx aea aec aee aeg aei aeo aer aet aex ag- aga agc age agg agi ago agr agt agx ai- aia aic aie aig aii aio air ait aix aoa aoc aoe aog aoi aoo aor aot aox ar- ara arc are arg ari aro arr art arx at- ata atc ate atg ati ato atr att atx ax- axa axe axi axo axr axt axx c-- caa cac cae cag cai cao car cat cax cca ccc cce ccg cci cco ccr cct ccx ce- cea cec cee ceg cei ceo cer cet cex cga cgc cge cgg cgi cgo cgr cgt ci- cia cic cie cig cii cio cir cit cix co- coa coc coe cog coi coo cor cot cox cra crc cre crg cri cro crr crt crx cta ctc cte ctg cti cto ctr ctt ctx cxc cxi cxo cxr cxt cxx eaa eac eae eag eai eao ear eat eax ec- eca ecc ece ecg eci eco ecr ect ecx eea eec eee eeg eeo eer eet eex ega egc ege egg egi ego egr egt egx eia eic eie eig eii eio eir eit eix eo- eoa eoc eoe eog eoi eoo eor eot era erc ere erg eri ero err ert eta etc ete etg eti eto etr ett etx ex- exa exc exe exi exo exr ext exx gaa gac gae gag gai gao gar gat gca gcc gce gcg gci gco gcr gct ge- gea gec gee geg gei geo ger get gex gga ggc ggg ggi ggo ggr ggt gia gic gie gig gii gio gir git goa goc goe gog goi goo gor got gox gra grc gre grg gri gro grr grt grx gta gtc gte gtg gti gto gtr gtt gtx gxa gxt ia- iaa iac iae iag iai iao iar iat ica icc ice icg ici ico icr ict ie- iea iec iee ieg iei ier iet iex iga igc ige igg igi igo igr igt iia iic iie iii iio iir iit iix io- ioa ioc ioe iog ioi ioo ior iot ir- ira irc ire irg iri iro irr irt irx ita itc ite itg iti ito itt itx ixc ixe ixi o-i oaa oac oae oag oai oao oar oat oax oc- oca occ ocg oci oco ocr oct ocx oea oec oee oeg oei oeo oer oet oex oga ogc oge ogg ogi ogo ogt ogx oia oic oie oii oio oir oit oo- ooa ooc oog ooi ooo oor oot oox or- ora orc ore org ori oro orr ort orx ot- ota otc ote otg oti oto otr ott ox- oxa oxc oxi oxo oxt oxx ra- raa rac rae rag rai rao rar rat rax rca rcc rce rcg rci rco rcr rct rcx re- rea rec ree reg rei reo rer ret rex rga rgc rge rgg rgi rgo rgr rgt rgx ria ric rie rig rii rio rir rit rix roa roc roe rog roi roo ror rot rox rra rrc rrg rri rrr rrt rta rtc rte rtg rti rto rtr rtt rtx rxr t-x taa tac tae tag tai tao tar tat tax tca tcc tce tcg tci tco tcr tct tcx te- tea tec tee teg tei teo ter tet tex tga tgc tge tgg tgi tgo tgr tgt tia tic tie tig tii tio tir tit tix to- toa toc toe tog toi too tor tot tox tra trc tre trg tri tro trr trt trx tta ttc tte ttg tti tto ttr ttt ttx txe txi txt xaa xac xag xar xat xci xcr xcx xee xeg xer xet xex xge xgi xia xic xie xii xio xit xix xoa xoc xog xoi xoo xor xot xox xrc xrt xrx xtc xti xtr xtx xxi xxo xxx