a-a a-b a-c a-t aaa aab aac aan aao aas aat aay ab- aba abb abc abn abo abs abt aby ac- aca acb acc acn aco acs act acy an- ana anb anc ann ano ans ant any aoa aob aoc aon aoo aos aot as- asa asb asc asn aso ass ast asy at- ata atb atc atn ato ats att ay- aya ayc ayn ayo ays ayt baa bab bac ban bao bas bat bay bba bbb bbc bbn bbo bbs bbt bby bca bcb bcc bcn bco bcs bct bcy bna bnb bnc bnn bno bns bnt boa bob boc bon boo bos bot boy bsa bsb bsc bsn bso bss bst bsy bta btb btc btn bto bts btt bty by- bya byc byn byo bys byt c-- caa cab cac can cao cas cat cay cba cbb cbc cbn cbo cbs cbt cby cca ccb ccc ccn cco ccs cct cn- cna cnb cnc cnn cno cns cnt cny co- coa cob coc con coo cos cot coy csa csb csc csn cso css cst csy cta ctb ctc ctn cto cts ctt cty cya cyb cyc cyn cyo cys cyt naa nab nac nan nao nas nat nay nba nbb nbc nbn nbo nbs nbt nca ncb ncc ncn nco ncs nct nna nnb nnc nnn nno nns nnt no- noa nob noc non noo nos not noy nsa nsb nsc nsn nso nss nst nsy nta ntb ntc ntn nto nts ntt nya nyc nyn nyo nys nyt nyy oaa oab oac oan oao oas oat ob- oba obb obc obn obo obs obt oby oc- oca ocb occ ocn oco ocs oct on- ona onb onc onn ono ons ont ony oo- ooa oob ooc oon ooo oos oot os- osa osb osc osn oso oss ost ot- ota otb otc otn oto ots ott oya oyo oys saa sab sac san sao sas sat say sba sbb sbc sbn sbo sbs sbt sby sca scb scc scn sco scs sct sna snb snc snn sno sns snt sny soa sob soc son soo sos sot soy ss- ssa ssb ssc ssn sso sss sst sta stb stc stn sto sts stt sty sy- sya syb syc syn sys syt taa tab tac tan tao tas tat tay tba tbb tbc tbn tbo tbs tbt tca tcb tcc tcn tco tcs tct tna tnb tnc tnn tno tns tnt to- toa tob toc ton too tos tot toy tsa tsb tsc tsn tso tss tst tsy tta ttb ttc ttn tto tts ttt tty tya tyc tyn tyo tys tyt yaa yab yac yan yao yas yat yay ybc ybs yby yca ycc yco ycs ycy yna ynn yns yny yob yoc yon yoo yos yot yoy ysa ysb ysc yso yss yst ysy yta ytc ytn yto yts ytt yyb yyc yys yyt yyy