-er eee eef eeo eer eet eex ef- efe eff efo efr eft efx eo- eoe eof eoo eor eot eou ere erf ero err ert eru ete etf eto etr ett etu etx eu- eue euf eur eut eux ex- exe exo exr ext exu exx fee fef feo fer fet feu fex ffe fff ffo ffr fft ffu ffx foe fof foo for fot fou fox fre frf fro frr frt fru fte ftf fto ftr ftt ftu ftx fue fuf fuo fur fut fuu fux fxe fxr fxt fxu fxx oee oef oeo oer oet oex of- ofe off ofo ofr oft ofu ofx oo- oof ooo oor oot oox or- ore orf oro orr ort oru orx ot- ote otf oto otr ott otu ou- oue ouf ouo our out ox- oxf oxo oxt oxx re- ree ref reo rer ret reu rex rfe rff rfo rfr rft rfu roe rof roo ror rot rou rox rrf rrr rrt rru rte rtf rto rtr rtt rtu rtx rue ruf ruo rur rut ruu rux rxr t-x te- tee tef teo ter tet teu tex tfe tff tfo tfr tft tfu tfx to- toe tof too tor tot tou tox tre trf tro trr trt tru trx tte ttf tto ttr ttt ttu ttx tue tuf tuo tur tut tuu tux txe txf txt txu uee uef uer uet ufe uff ufo ufr uft ufu ufx uoe uoo uor uot uox ur- ure urf uro urr urt uru urx ute utf uto utr utt utu utx uue uur uut uuu uxf uxo uxr uxt uxu xee xer xet xeu xex xfe xft xfx xof xoo xor xot xox xrf xrt xrx xtf xtr xtx xue xxo xxx