-er a-a a-b aaa aab aae aaf aag aan aao aap aar ab- aba abb abe abf abg abn abo abp abr aea aeb aee aef aeg aen aeo aep aer af- afa afb afe aff afg afn afo afp afr ag- aga agb age agf agg agn ago agp agr an- ana anb ane anf ang ann ano anp anr aoa aob aoe aof aog aon aoo aop aor ap- apa apb ape apf apg apn apo app apr ar- ara arb are arf arg arn aro arp arr b-p baa bab bae baf bag ban bao bap bar bba bbb bbe bbf bbg bbn bbo bbp bbr be- bea beb bee bef beg ben beo bep ber bfa bfb bfe bff bfg bfn bfo bfp bfr bga bgb bge bgf bgg bgn bgo bgp bgr bna bnb bne bnf bng bnn bno bnp bnr boa bob boe bof bog bon boo bop bor bpa bpb bpe bpf bpg bpn bpo bpp bpr bra brb bre brf brg brn bro brp brr eaa eab eae eaf eag ean eao eap ear eba ebb ebe ebf ebg ebn ebo ebp ebr eea eeb eee eef eeg een eeo eep eer ef- efa efb efe eff efg efo efp efr ega egb ege egf egg egn ego egp egr en- ena enb ene enf eng enn eno enp enr eo- eoa eob eoe eof eog eon eoo eop eor ep- epa epb epe epf epg epn epo epp epr era erb ere erf erg ern ero erp err faa fab fae faf fag fan fao fap far fba fbb fbe fbf fbg fbn fbo fbp fbr fea feb fee fef feg fen feo fep fer ffa ffe fff ffg ffn ffo ffp ffr fga fgb fge fgf fgg fgn fgp fgr fna fnb fne fnf fng fnn fnp fnr foa fob foe fof fog fon foo fop for fpa fpb fpe fpg fpn fpo fpp fpr fra frb fre frf frg frn fro frp frr g-p gaa gab gae gaf gag gan gao gap gar gba gbe gbf gbg gbn gbo gbp gbr ge- gea geb gee gef geg gen geo gep ger gfa gfb gfe gff gfo gfp gfr gga ggb ggg ggn ggo ggp ggr gna gnb gne gnf gnn gno gnp gnr goa gob goe gof gog gon goo gop gor gpa gpb gpe gpf gpg gpn gpo gpp gpr gra grb gre grf grg grn gro grp grr naa nab nae naf nag nan nao nap nar nba nbb nbe nbf nbg nbn nbo nbp nbr ne- nea neb nee nef neg nen neo nep ner nfa nfb nfe nff nfn nfo nfp nfr nga ngb nge ngf ngg ngn ngo ngp nna nnb nne nnf nng nnn nno nnp no- noa nob noe nof nog non noo nop nor npa npb npe npf npg npn npo npp npr nra nrb nre nrf nrg nrn nro nrp nrr oaa oab oae oaf oag oan oao oap oar ob- oba obb obe obf obg obn obo obp obr oea oeb oee oef oeg oen oeo oep oer of- ofa ofb ofe off ofg ofn ofo ofp ofr oga oge ogf ogg ogn ogo ogp on- ona onb one onf ong onn ono onp onr oo- ooa oob oof oog oon ooo oop oor op- opa opb ope opf opg opn opo opp opr or- ora orb ore orf org orn oro orp orr p-p paa pab pae paf pag pan pao pap par pba pbb pbe pbf pbg pbn pbo pbp pbr pea peb pee pef peg pen peo pep per pfa pfb pfe pff pfg pfn pfo pfp pfr pga pgb pge pgf pgg pgn pgo pgp pgr pn- pna pnb pne pnf png pnn pno pnp pnr poa pob poe pof pog pon poo pop por ppa ppb ppe ppf ppg ppn ppo ppp ppr pra prb pre prf prg prn pro prp prr ra- raa rab rae raf rag ran rao rap rar rba rbb rbe rbf rbg rbn rbo rbp rbr re- rea reb ree ref reg ren reo rep rer rfa rfb rfe rff rfg rfn rfo rfp rfr rga rgb rge rgf rgg rgn rgo rgp rgr rna rnb rng rnn rno rnp rnr roa rob roe rof rog ron roo rop ror rpa rpb rpe rpf rpg rpn rpo rpp rpr rra rrb rrf rrg rrn rrp rrr