a-a a-b a-c aaa aab aac aag aar aau aay ab- aba abb abc abg abr abu aby ac- aca acb acc acg acr acu acy ag- aga agb agc agg agr agu agy ar- ara arb arc arg arr aru ary au- aua aub auc aug aur ay- aya ayc ayr ayu b-u baa bab bac bag bar bau bay bba bbb bbc bbg bbr bbu bby bca bcb bcc bcg bcr bcu bcy bga bgb bgc bgg bgr bgu bra brb brg brr bru bry bua bub buc bug bur buu buy by- bya byc byg byr byu c-- caa cab cac cag car cau cay cba cbb cbc cbg cbr cbu cby cca ccb ccc ccg ccr ccu cga cgb cgc cgg cgr cgu cgy cra crb crc crg crr cru cry cua cub cuc cug cur cuu cuy cya cyb cyc cyg cyr gaa gab gac gag gar gau gay gba gbc gbg gbr gbu gby gca gcb gcc gcg gcr gcu gga ggb ggc ggg ggr ggu gra grb grc grg grr gru gry gu- gua gub guc gug gur guu guy gy- gya gyb gyr ra- raa rab rac rag rar rau ray rba rbb rbc rbg rbr rbu rca rcb rcc rcg rcr rcu rga rgb rgc rgg rgr rra rrb rrc rrg rrr rru rua rub ruc rug rur ruu ruy ry- rya ryc ryg ryr ryu ryy ua- uaa uab uac uag uar uau uay uba ubb ubc ubg ubr ubu uby uca ucb ucc ucg ucr ucu uga ugb ugc ugg ugr ugu ur- ura urb urc urg urr uru ury uua uuc uug uur uuu uyc uyu yaa yab yac yag yar yau yay ybc ybg ybr yby yca ycc ycu ycy yga ygc yra yrc yrg yru yua yug yur yuu yuy yyb yyc yyg yyu yyy