a-a a-b a-t aaa aab aap aar aat aay ab- aba abb abp abr abt aby ap- apa apb app apr apt apy ar- ara arb arp arr art ary at- ata atb atp atr att ay- aya ayp ayr ayt b-p baa bab bap bar bat bay bba bbb bbp bbr bbt bby bpa bpb bpp bpr bpt bpy bra brb brp brr brt bry bta btb btp btr btt bty by- bya byp byr byt p-p paa pab pap par pat pay pba pbb pbp pbr pbt pby ppa ppb ppp ppr ppt pra prb prp prr prt pry pt- pta ptb ptp ptr ptt pty py- pya pyb pyr pyt ra- raa rab rap rar rat ray rba rbb rbp rbr rbt rpa rpb rpp rpr rpt rra rrb rrp rrr rrt rta rtb rtp rtr rtt rty ry- rya ryr ryy taa tab tap tar tat tay tba tbb tbp tbr tbt tpa tpb tpp tpr tpt tra trb trp trr trt try tta ttb ttp ttr ttt tty tya typ tyr tyt yaa yab yap yar yat yay ybp ybr yby ypa yra yrp yrt yta ytp ytr ytt yyb yyt yyy