-er a-a a-b aaa aab aad aae aag aao aar aav ab- aba abb abd abe abg abo abr abv ad- ada adb add ade adg ado adr adv aea aeb aed aee aeg aeo aer aev ag- aga agb agd age agg ago agr agv aoa aob aod aoe aog aoo aor aov ar- ara arb ard are arg aro arr arv av- ava avb avd ave avg avo avr baa bab bad bae bag bao bar bav bba bbb bbd bbe bbg bbo bbr bda bdb bdd bde bdg bdo bdr bdv be- bea beb bed bee beg beo ber bev bga bgb bgd bge bgg bgo bgr bgv boa bob bod boe bog boo bor bov bra brb brd bre brg bro brr brv bva bvb bvd bve bvg bvo bvr bvv daa dab dad dae dag dao dar dav dba dbb dbd dbe dbg dbo dbr dbv dda ddb ddd dde ddg ddo ddr de- dea deb ded dee deg deo der dev dga dgd dge dgg dgr doa dob dod doe dog doo dor dov dra drb drd dre drg dro drr drv dva dvb dvd dve dvg dvr eaa eab ead eae eag eao ear eav eba ebb ebd ebe ebg ebo ebr ebv ed- eda edb edd ede edg edo edr eea eeb eed eee eeg eeo eer eev ega egb egd ege egg ego egr eo- eoa eob eod eoe eog eoo eor era erb erd ere erg ero err erv eva evb evd eve evg evo evr evv g-d gaa gab gad gae gag gao gar gav gba gbd gbe gbg gbo gbr gbv gda gdb gdd gde gdo gdr gdv ge- gea geb ged gee geg geo ger gev gga ggb ggd ggg ggo ggr ggv goa gob god goe gog goo gor gov gra grb grd gre grg gro grr grv gva gvb gvd gve gvg gvo gvr oaa oab oad oae oag oao oar oav ob- oba obb obd obe obg obo obr obv oda odb odd ode odg odo odr odv oea oeb oed oee oeg oeo oer oga ogd oge ogg ogo oo- ooa oob ood oog ooo oor oov or- ora orb ord ore org oro orr orv ov- ova ovb ovd ove ovo ovv ra- raa rab rad rae rag rao rar rav rba rbb rbd rbe rbg rbo rbr rda rdb rdd rde rdg rdo rdr rdv re- rea reb red ree reg reo rer rev rga rgb rgd rge rgg rgo rgr rgv roa rob rod roe rog roo ror rov rra rrb rrd rrg rrr rva rvb rvd rve rvg rvo rvr rvv v-a v-e vaa vab vad vae vag vao var vav vba vbd vbg vbo vbr vbv vdb vdd vde vdg vdo vdr vdv vea veb ved vee veg veo ver vga vgg vgo vgr voa vob vod voe vog voo vor vov vra vrb vrd vre vrg vrr vva vvb vvg vvo vvr vvv