-er a-a a-c aaa aac aae aag aan aao aap aar ac- aca acc ace acg acn aco acp acr aea aec aee aeg aen aeo aep aer ag- aga agc age agg agn ago agp agr an- ana anc ane ang ann ano anp anr aoa aoc aoe aog aon aoo aop aor ap- apa apc ape apg apn apo app apr ar- ara arc are arg arn aro arp arr c-- caa cac cae cag can cao cap car cca ccc cce ccg ccn cco ccp ccr ce- cea cec cee ceg cen ceo cep cer cga cgc cge cgg cgn cgo cgp cgr cn- cna cnc cne cng cnn cno cnp cnr co- coa coc coe cog con coo cop cor cpa cpc cpe cpg cpn cpo cpp cpr cra crc cre crg crn cro crp crr eaa eac eae eag ean eao eap ear ec- eca ecc ece ecg ecn eco ecr eea eec eee eeg een eeo eep eer ega egc ege egg egn ego egp egr en- ena enc ene eng enn eno enp enr eo- eoa eoc eoe eog eon eoo eop eor ep- epa epc epe epg epn epo epp epr era erc ere erg ern ero erp err g-p gaa gac gae gag gan gao gap gar gca gcc gce gcg gcn gco gcp gcr ge- gea gec gee geg gen geo gep ger gga ggc ggg ggn ggo ggp ggr gna gnc gne gnn gno gnp gnr goa goc goe gog gon goo gop gor gpa gpc gpe gpg gpn gpo gpp gpr gra grc gre grg grn gro grp grr naa nac nae nag nan nao nap nar nca ncc nce ncg ncn nco ncp ncr ne- nea nec nee neg nen neo nep ner nga ngc nge ngg ngn ngo ngp nna nnc nne nng nnn nno nnp no- noa noc noe nog non noo nop nor npa npc npe npg npn npo npp npr nra nrc nre nrg nrn nro nrp nrr oaa oac oae oag oan oao oap oar oc- oca occ ocg ocn oco ocp ocr oea oec oee oeg oen oeo oep oer oga ogc oge ogg ogn ogo ogp on- ona onc one ong onn ono onp onr oo- ooa ooc oog oon ooo oop oor op- opa opc ope opg opn opo opp opr or- ora orc ore org orn oro orp orr p-p paa pac pae pag pan pao pap par pca pcc pce pcg pcn pco pcp pcr pea pec pee peg pen peo pep per pga pgc pge pgg pgn pgo pgp pgr pn- pna pnc pne png pnn pno pnp pnr poa poc poe pog pon poo pop por ppa ppc ppe ppg ppn ppo ppp ppr pra prc pre prg prn pro prp prr ra- raa rac rae rag ran rao rap rar rca rcc rce rcg rcn rco rcp rcr re- rea rec ree reg ren reo rep rer rga rgc rge rgg rgn rgo rgp rgr rna rnc rng rnn rno rnp rnr roa roc roe rog ron roo rop ror rpa rpc rpe rpg rpn rpo rpp rpr rra rrc rrg rrn rrp rrr