-er a-a a-b a-c a-t aaa aab aac aae aag aar aat aav ab- aba abb abc abe abg abr abt abv ac- aca acb acc ace acg acr act acv aea aeb aec aee aeg aer aet aev ag- aga agb agc age agg agr agt agv ar- ara arb arc are arg arr art arv at- ata atb atc ate atg atr att atv av- ava avb avc ave avg avr avt baa bab bac bae bag bar bat bav bba bbb bbc bbe bbg bbr bbt bca bcb bcc bce bcg bcr bct bcv be- bea beb bec bee beg ber bet bev bga bgb bgc bge bgg bgr bgt bgv bra brb bre brg brr brt brv bta btb btc bte btg btr btt btv bva bvb bvc bve bvg bvr bvt bvv c-- caa cab cac cae cag car cat cav cba cbb cbc cbe cbg cbr cbt cbv cca ccb ccc cce ccg ccr cct ccv ce- cea ceb cec cee ceg cer cet cev cga cgb cgc cge cgg cgr cgt cgv cra crb crc cre crg crr crt crv cta ctb ctc cte ctg ctr ctt ctv cva cvb cvc cve cvg cvr cvt cvv eaa eab eac eae eag ear eat eav eba ebb ebc ebe ebg ebr ebt ebv ec- eca ecb ecc ece ecg ecr ect ecv eea eeb eec eee eeg eer eet eev ega egb egc ege egg egr egt era erb erc ere erg err ert erv eta etb etc ete etg etr ett etv eva evb evc eve evg evr evt evv gaa gab gac gae gag gar gat gav gba gbc gbe gbg gbr gbt gbv gca gcb gcc gce gcg gcr gct ge- gea geb gec gee geg ger get gev gga ggb ggc ggg ggr ggt ggv gra grb grc gre grg grr grt grv gta gtb gtc gte gtg gtr gtt gtv gva gvb gvc gve gvg gvr gvt ra- raa rab rac rae rag rar rat rav rba rbb rbc rbe rbg rbr rbt rca rcb rcc rce rcg rcr rct rcv re- rea reb rec ree reg rer ret rev rga rgb rgc rge rgg rgr rgt rgv rra rrb rrc rrg rrr rrt rta rtb rtc rte rtg rtr rtt rtv rva rvb rvc rve rvg rvr rvt rvv taa tab tac tae tag tar tat tav tba tbb tbc tbe tbg tbr tbt tbv tca tcb tcc tce tcg tcr tct tcv te- tea teb tec tee teg ter tet tev tga tgb tgc tge tgg tgr tgt tgv tra trb trc tre trg trr trt trv tta ttb ttc tte ttg ttr ttt ttv tva tvb tvc tve tvg tvr tvt v-a v-e vaa vab vac vae vag var vat vav vba vbc vbg vbr vbv vca vcc vce vcr vct vea veb vec vee veg ver vet vga vgc vgg vgr vgt vra vrb vrc vre vrg vrr vrt vta vtb vtc vte vtg vtr vtt vtv vva vvb vvc vvg vvr vvt vvv