-er a-a a-b a-c aaa aab aac aae aag aan aar aau ab- aba abb abc abe abg abn abr abu ac- aca acb acc ace acg acn acr acu aea aeb aec aee aeg aen aer aeu ag- aga agb agc age agg agn agr agu an- ana anb anc ane ang ann anr anu ar- ara arb arc are arg arn arr aru au- aua aub auc aue aug aun aur b-u baa bab bac bae bag ban bar bau bba bbb bbc bbe bbg bbn bbr bbu bca bcb bcc bce bcg bcn bcr bcu be- bea beb bec bee beg ben ber beu bga bgb bgc bge bgg bgn bgr bgu bna bnb bnc bne bng bnn bnr bnu bra brb bre brg brn brr bru bua bub buc bue bug bun bur buu c-- caa cab cac cae cag can car cau cba cbb cbc cbe cbg cbn cbr cbu cca ccb ccc cce ccg ccn ccr ccu ce- cea ceb cec cee ceg cen cer ceu cga cgb cgc cge cgg cgn cgr cgu cn- cna cnb cnc cne cng cnn cnr cnu cra crb crc cre crg crn crr cru cua cub cuc cue cug cun cur cuu eaa eab eac eae eag ean ear eau eba ebb ebc ebe ebg ebn ebr ebu ec- eca ecb ecc ece ecg ecn ecr ecu eea eeb eec eee eeg een eer ega egb egc ege egg egn egr egu en- ena enb enc ene eng enn enr enu era erb erc ere erg ern err eru eu- eua eub euc eue eug eun eur gaa gab gac gae gag gan gar gau gba gbc gbe gbg gbn gbr gbu gca gcb gcc gce gcg gcn gcr gcu ge- gea geb gec gee geg gen ger geu gga ggb ggc ggg ggn ggr ggu gna gnb gnc gne gnn gnr gnu gra grb grc gre grg grn grr gru gu- gua gub guc gue gug gun gur guu naa nab nac nae nag nan nar nau nba nbb nbc nbe nbg nbn nbr nbu nca ncb ncc nce ncg ncn ncr ncu ne- nea neb nec nee neg nen ner neu nga ngb ngc nge ngg ngn ngu nna nnb nnc nne nng nnn nnu nra nrb nrc nre nrg nrn nrr nru nua nub nuc nue nug nun nur nuu ra- raa rab rac rae rag ran rar rau rba rbb rbc rbe rbg rbn rbr rbu rca rcb rcc rce rcg rcn rcr rcu re- rea reb rec ree reg ren rer reu rga rgb rgc rge rgg rgn rgr rna rnb rnc rng rnn rnr rnu rra rrb rrc rrg rrn rrr rru rua rub ruc rue rug run rur ruu ua- uaa uab uac uae uag uan uar uau uba ubb ubc ube ubg ubn ubr ubu uca ucb ucc uce ucg ucn ucr ucu uea ueb uec uee ueg uen uer uga ugb ugc uge ugg ugn ugr ugu un- una unb unc une ung unn unr unu ur- ura urb urc ure urg urn urr uru uua uuc uue uug uun uur uuu