-er a-a a-b a-c aaa aab aac aae aag aap aar ab- aba abb abc abe abg abp abr ac- aca acb acc ace acg acp acr aea aeb aec aee aeg aep aer ag- aga agb agc age agg agp agr ap- apa apb apc ape apg app apr ar- ara arb arc are arg arp arr b-p baa bab bac bae bag bap bar bba bbb bbc bbe bbg bbp bbr bca bcb bcc bce bcg bcp bcr be- bea beb bec bee beg bep ber bga bgb bgc bge bgg bgp bgr bpa bpb bpc bpe bpg bpp bpr bra brb bre brg brp brr c-- caa cab cac cae cag cap car cba cbb cbc cbe cbg cbp cbr cca ccb ccc cce ccg ccp ccr ce- cea ceb cec cee ceg cep cer cga cgb cgc cge cgg cgp cgr cpa cpb cpc cpe cpg cpp cpr cra crb crc cre crg crp crr eaa eab eac eae eag eap ear eba ebb ebc ebe ebg ebp ebr ec- eca ecb ecc ece ecg ecr eea eeb eec eee eeg eep eer ega egb egc ege egg egp egr ep- epa epb epc epe epg epp epr era erb erc ere erg erp err g-p gaa gab gac gae gag gap gar gba gbc gbe gbg gbp gbr gca gcb gcc gce gcg gcp gcr ge- gea geb gec gee geg gep ger gga ggb ggc ggg ggp ggr gpa gpb gpc gpe gpg gpp gpr gra grb grc gre grg grp grr p-p paa pab pac pae pag pap par pba pbb pbc pbe pbg pbp pbr pca pcb pcc pce pcg pcp pcr pea peb pec pee peg pep per pga pgb pgc pge pgg pgp pgr ppa ppb ppc ppe ppg ppp ppr pra prb prc pre prg prp prr ra- raa rab rac rae rag rap rar rba rbb rbc rbe rbg rbp rbr rca rcb rcc rce rcg rcp rcr re- rea reb rec ree reg rep rer rga rgb rgc rge rgg rgp rgr rpa rpb rpc rpe rpg rpp rpr rra rrb rrc rrg rrp rrr