-er a-a a-b a-c a-t aaa aab aac aae aag aap aar aat ab- aba abb abc abe abg abp abr abt ac- aca acb acc ace acg acp acr act aea aeb aec aee aeg aep aer aet ag- aga agb agc age agg agp agr agt ap- apa apb apc ape apg app apr apt ar- ara arb arc are arg arp arr art at- ata atb atc ate atg atp atr att b-p baa bab bac bae bag bap bar bat bba bbb bbc bbe bbg bbp bbr bbt bca bcb bcc bce bcg bcp bcr bct be- bea beb bec bee beg bep ber bet bga bgb bgc bge bgg bgp bgr bgt bpa bpb bpc bpe bpg bpp bpr bpt bra brb bre brg brp brr brt bta btb btc bte btg btp btr btt c-- caa cab cac cae cag cap car cat cba cbb cbc cbe cbg cbp cbr cbt cca ccb ccc cce ccg ccp ccr cct ce- cea ceb cec cee ceg cep cer cet cga cgb cgc cge cgg cgp cgr cgt cpa cpb cpc cpe cpg cpp cpr cpt cra crb crc cre crg crp crr crt cta ctb ctc cte ctg ctp ctr ctt eaa eab eac eae eag eap ear eat eba ebb ebc ebe ebg ebp ebr ebt ec- eca ecb ecc ece ecg ecr ect eea eeb eec eee eeg eep eer eet ega egb egc ege egg egp egr egt ep- epa epb epc epe epg epp epr ept era erb erc ere erg erp err ert eta etb etc ete etg etp etr ett g-p gaa gab gac gae gag gap gar gat gba gbc gbe gbg gbp gbr gbt gca gcb gcc gce gcg gcp gcr gct ge- gea geb gec gee geg gep ger get gga ggb ggc ggg ggp ggr ggt gpa gpb gpc gpe gpg gpp gpr gpt gra grb grc gre grg grp grr grt gta gtb gtc gte gtg gtp gtr gtt p-p paa pab pac pae pag pap par pat pba pbb pbc pbe pbg pbp pbr pbt pca pcb pcc pce pcg pcp pcr pct pea peb pec pee peg pep per pet pga pgb pgc pge pgg pgp pgr pgt ppa ppb ppc ppe ppg ppp ppr ppt pra prb prc pre prg prp prr prt pt- pta ptb ptc pte ptg ptp ptr ptt ra- raa rab rac rae rag rap rar rat rba rbb rbc rbe rbg rbp rbr rbt rca rcb rcc rce rcg rcp rcr rct re- rea reb rec ree reg rep rer ret rga rgb rgc rge rgg rgp rgr rgt rpa rpb rpc rpe rpg rpp rpr rpt rra rrb rrc rrg rrp rrr rrt rta rtb rtc rte rtg rtp rtr rtt taa tab tac tae tag tap tar tat tba tbb tbc tbe tbg tbp tbr tbt tca tcb tcc tce tcg tcp tcr tct te- tea teb tec tee teg tep ter tet tga tgb tgc tge tgg tgp tgr tgt tpa tpb tpc tpe tpg tpp tpr tpt tra trb trc tre trg trp trr trt tta ttb ttc tte ttg ttp ttr ttt