-er a-a a-b a-c aaa aab aac aae aag aah aan aar ab- aba abb abc abe abg abh abn abr ac- aca acb acc ace acg ach acn acr aea aeb aec aee aeg aeh aen aer ag- aga agb agc age agg agh agn agr aha ahb ahc ahe ahg ahh ahn ahr an- ana anb anc ane ang anh ann anr ar- ara arb arc are arg arh arn arr baa bab bac bae bag bah ban bar bba bbb bbc bbe bbg bbh bbn bbr bca bcb bcc bce bcg bch bcn bcr be- bea beb bec bee beg beh ben ber bga bgb bgc bge bgg bgh bgn bgr bha bhb bhc bhe bhg bhh bhr bna bnb bnc bne bng bnn bnr bra brb bre brg brh brn brr c-- caa cab cac cae cag cah can car cba cbb cbc cbe cbg cbh cbn cbr cca ccb ccc cce ccg cch ccn ccr ce- cea ceb cec cee ceg ceh cen cer cga cgb cgc cge cgg cgh cgn cgr ch- cha chb chc che chg chh chn chr cn- cna cnb cnc cne cng cnh cnn cnr cra crb crc cre crg crh crn crr eaa eab eac eae eag eah ean ear eba ebb ebc ebe ebg ebh ebn ebr ec- eca ecb ecc ece ecg ech ecn ecr eea eeb eec eee eeg een eer ega egb egc ege egg egh egn egr eha ehb ehc ehe ehg ehh ehn ehr en- ena enb enc ene eng enh enn enr era erb erc ere erg erh ern err gaa gab gac gae gag gah gan gar gba gbc gbe gbg gbh gbn gbr gca gcb gcc gce gcg gch gcn gcr ge- gea geb gec gee geg geh gen ger gga ggb ggc ggg ggh ggn ggr gha ghb ghc ghe ghg ghh ghn ghr gna gnb gnc gne gnn gnr gra grb grc gre grg grh grn grr haa hab hac hae hag hah han har hba hbb hbc hbe hbg hbh hbn hbr hca hcb hcc hce hcg hch hcn hcr he- hea heb hec hee heg heh hen her hga hgb hgc hge hgg hgh hgn hgr hha hhb hhc hhe hhg hhh hhn hhr hna hnb hnc hne hng hnh hnn hr- hra hrb hrc hre hrg hrh hrn hrr naa nab nac nae nag nah nan nar nba nbb nbc nbe nbg nbn nbr nca ncb ncc nce ncg nch ncn ncr ne- nea neb nec nee neg neh nen ner nga ngb ngc nge ngg ngh ngn nha nhb nhc nhe nhg nhh nhn nhr nna nnb nnc nne nng nnh nnn nra nrb nrc nre nrg nrn nrr ra- raa rab rac rae rag rah ran rar rba rbb rbc rbe rbg rbh rbn rbr rca rcb rcc rce rcg rch rcn rcr re- rea reb rec ree reg reh ren rer rga rgb rgc rge rgg rgh rgn rgr rh- rha rhb rhc rhe rhg rhh rhn rhr rna rnb rnc rng rnh rnn rnr rra rrb rrc rrg rrh rrn rrr