-er a-a a-c aaa aac aae aag aah aan aao aar aax ac- aca acc ace acg ach acn aco acr acx aea aec aee aeg aeh aen aeo aer aex ag- aga agc age agg agh agn ago agr agx aha ahc ahe ahg ahh ahn aho ahr ahx an- ana anc ane ang anh ann ano anr anx aoa aoc aoe aog aoh aon aoo aor aox ar- ara arc are arg arh arn aro arr arx ax- axa axe axh axn axo axr axx c-- caa cac cae cag cah can cao car cax cca ccc cce ccg cch ccn cco ccr ccx ce- cea cec cee ceg ceh cen ceo cer cex cga cgc cge cgg cgh cgn cgo cgr ch- cha chc che chg chh chn cho chr chx cn- cna cnc cne cng cnh cnn cno cnr cnx co- coa coc coe cog coh con coo cor cox cra crc cre crg crh crn cro crr crx cxc cxh cxo cxr cxx eaa eac eae eag eah ean eao ear eax ec- eca ecc ece ecg ech ecn eco ecr ecx eea eec eee eeg een eeo eer eex ega egc ege egg egh egn ego egr egx eha ehc ehe ehg ehh ehn eho ehr en- ena enc ene eng enh enn eno enr eo- eoa eoc eoe eog eoh eon eoo eor era erc ere erg erh ern ero err ex- exa exc exe exh exo exr exx gaa gac gae gag gah gan gao gar gca gcc gce gcg gch gcn gco gcr ge- gea gec gee geg geh gen geo ger gex gga ggc ggg ggh ggn ggo ggr gha ghc ghe ghg ghh ghn gho ghr gna gnc gne gnn gno gnr goa goc goe gog goh gon goo gor gox gra grc gre grg grh grn gro grr grx gxa haa hac hae hag hah han hao har hax hca hcc hce hcg hch hcn hco hcr he- hea hec hee heg heh hen heo her hex hga hgc hge hgg hgh hgn hgo hgr hha hhc hhe hhg hhh hhn hho hhr hna hnc hne hng hnh hnn hno hoa hoc hoe hog hoh hon hoo hor hox hr- hra hrc hre hrg hrh hrn hro hrr hxc naa nac nae nag nah nan nao nar nax nca ncc nce ncg nch ncn nco ncr ncx ne- nea nec nee neg neh nen neo ner nex nga ngc nge ngg ngh ngn ngo nha nhc nhe nhg nhh nhn nhr nna nnc nne nng nnh nnn nno no- noa noc noe nog noh non noo nor nox nra nrc nre nrg nrn nro nrr nrx nxc oaa oac oae oag oah oan oao oar oax oc- oca occ ocg och ocn oco ocr ocx oea oec oee oeg oeh oen oeo oer oex oga ogc oge ogg ogh ogn ogo ogx oha ohc ohe ohg ohh ohn oho ohr on- ona onc one ong onh onn ono onr onx oo- ooa ooc oog ooh oon ooo oor oox or- ora orc ore org orh orn oro orr orx ox- oxa oxc oxn oxo oxx ra- raa rac rae rag rah ran rao rar rax rca rcc rce rcg rch rcn rco rcr rcx re- rea rec ree reg reh ren reo rer rex rga rgc rge rgg rgh rgn rgo rgr rgx rh- rha rhc rhe rhg rhh rhn rho rhr rna rnc rng rnh rnn rno rnr roa roc roe rog roh ron roo ror rox rra rrc rrg rrh rrn rrr rxr xaa xac xag xan xar xch xcr xcx xee xeg xen xer xex xge xna xnc xno xoa xoc xog xon xoo xor xox xrc xrx xxo xxx