a-a a-b a-z aaa aab aag aan aao aar aaz ab- aba abb abg abn abo abr abz ag- aga agb agg agn ago agr agz an- ana anb ang ann ano anr anz aoa aob aog aon aoo aor ar- ara arb arg arn aro arr arz az- aza azb azg azn azo azz baa bab bag ban bao bar baz bba bbb bbg bbn bbo bbr bga bgb bgg bgn bgo bgr bgz bna bnb bng bnn bno bnr bnz boa bob bog bon boo bor boz bra brb brg brn bro brr brz bza bzn bzo bzr bzz gaa gab gag gan gao gar gaz gba gbg gbn gbo gbr gbz gga ggb ggg ggn ggo ggr ggz gna gnb gnn gno gnr goa gob gog gon goo gor goz gra grb grg grn gro grr gza gzo gzr naa nab nag nan nao nar naz nba nbb nbg nbn nbo nbr nga ngb ngg ngn ngo nna nnb nng nnn nno nnz no- noa nob nog non noo nor noz nra nrb nrg nrn nro nrr nrz nzb nzg nzo nzz oaa oab oag oan oao oar ob- oba obb obg obn obo obr oga ogg ogn ogo on- ona onb ong onn ono onr oo- ooa oob oog oon ooo oor or- ora orb org orn oro orr orz oza ozo ozz ra- raa rab rag ran rao rar raz rba rbb rbg rbn rbo rbr rga rgb rgg rgn rgo rgr rna rnb rng rnn rno rnr rnz roa rob rog ron roo ror roz rra rrb rrg rrn rrr rza rzb rzo z-g zaa zab zag zan zao zar zaz zbb zbr zgb zgg znn zno zo- zoa zob zog zon zoo zor zro zzr zzz