a-a a-b a-z aaa aab aap aar aay aaz ab- aba abb abp abr aby abz ap- apa apb app apr apy ar- ara arb arp arr ary arz ay- aya ayp ayr ayz az- aza azb azp azy azz b-p baa bab bap bar bay baz bba bbb bbp bbr bby bpa bpb bpp bpr bpy bra brb brp brr bry brz by- bya byp byr byz bza bzp bzr bzz p-p paa pab pap par pay paz pba pbb pbp pbr pby pbz ppa ppb ppp ppr ppz pra prb prp prr pry prz py- pya pyb pyr pzp ra- raa rab rap rar ray raz rba rbb rbp rbr rpa rpb rpp rpr rpz rra rrb rrp rrr ry- rya ryr ryy ryz rza rzb rzy yaa yab yap yar yay yaz ybp ybr yby ybz ypa yra yrp yyb yyy yyz yzb yzr yzy zaa zab zap zar zay zaz zbb zbr zby zpp zpr zrp zzr zzy zzz