a-a a-b a-c aaa aab aac aan aar aau aay ab- aba abb abc abn abr abu aby ac- aca acb acc acn acr acu acy an- ana anb anc ann anr anu any ar- ara arb arc arn arr aru ary au- aua aub auc aun aur ay- aya ayc ayn ayr ayu b-u baa bab bac ban bar bau bay bba bbb bbc bbn bbr bbu bby bca bcb bcc bcn bcr bcu bcy bna bnb bnc bnn bnr bnu bra brb brn brr bru bry bua bub buc bun bur buu buy by- bya byc byn byr byu c-- caa cab cac can car cau cay cba cbb cbc cbn cbr cbu cby cca ccb ccc ccn ccr ccu cn- cna cnb cnc cnn cnr cnu cny cra crb crc crn crr cru cry cua cub cuc cun cur cuu cuy cya cyb cyc cyn cyr naa nab nac nan nar nau nay nba nbb nbc nbn nbr nbu nca ncb ncc ncn ncr ncu nna nnb nnc nnn nnu nra nrb nrc nrn nrr nru nry nua nub nuc nun nur nuu nuy nya nyc nyn nyu nyy ra- raa rab rac ran rar rau ray rba rbb rbc rbn rbr rbu rca rcb rcc rcn rcr rcu rna rnb rnc rnn rnr rnu rny rra rrb rrc rrn rrr rru rua rub ruc run rur ruu ruy ry- rya ryc ryn ryr ryu ryy ua- uaa uab uac uan uar uau uay uba ubb ubc ubn ubr ubu uby uca ucb ucc ucn ucr ucu un- una unb unc unn unr unu uny ur- ura urb urc urn urr uru ury uua uuc uun uur uuu uyc uyu yaa yab yac yan yar yau yay ybc ybr yby yca ycc ycu ycy yna ynn ynu yny yra yrc yrn yru yua yun yur yuu yuy yyb yyc yyu yyy