a-a a-b a-t aaa aab aad aak aan aao aas aat ab- aba abb abd abk abn abo abs abt ad- ada adb add adk adn ado ads adt aka akb akd akk akn ako aks an- ana anb and ank ann ano ans ant aoa aob aod aok aon aoo aos aot as- asa asb asd ask asn aso ass ast at- ata atb atd atn ato ats att baa bab bad bak ban bao bas bat bba bbb bbd bbk bbn bbo bbs bbt bda bdb bdd bdk bdo bds bdt bka bkb bkk bkn bko bks bkt bna bnb bnd bnk bnn bno bns bnt boa bob bod bok bon boo bos bot bsa bsb bsd bsk bsn bso bss bst bta btb btd btk btn bto bts btt daa dab dad dak dan dao das dat dba dbb dbd dbk dbn dbo dbs dbt dda ddb ddd ddk ddn ddo dds ddt dka dkb dkk dko dks dkt dna dnb dnd dnk dnn dno dns dnt doa dob dod dok don doo dos dot dsa dsb dsd dsk dsn dso dss dst dta dtb dtd dtk dtn dto dts dtt k-t ka- kaa kab kad kak kan kao kas kat kba kbb kbd kbk kbn kbo kbs kda kdb kdk kdo kds kdt kkb kkk kkn kks kkt kn- kna knd knk knn kno knt koa kob kod kok kon koo kos kot ksa ksb ksd ksk ksn kso kss kst kta ktb ktk ktn kto kts ktt naa nab nad nak nan nao nas nat nba nbb nbd nbk nbn nbo nbs nbt nda ndb ndd ndk ndn ndo nds ndt nka nkk nkn nko nks nkt nna nnb nnk nnn nno nns nnt no- noa nob nod nok non noo nos not nsa nsb nsd nsk nsn nso nss nst nta ntb ntd ntk ntn nto nts ntt oaa oab oad oak oan oao oas oat ob- oba obb obd obk obn obo obs obt oda odb odd odn odo ods odt oka okb okd okk oko oks on- ona onb ond onk onn ono ons ont oo- ooa oob ood ook oon ooo oos oot os- osa osb osd osk osn oso oss ost ot- ota otb otd otk otn oto ots ott saa sab sad sak san sao sas sat sba sbb sbd sbk sbn sbo sbs sbt sda sdb sdd sdk sdn sdo sds sdt sk- ska skb skd skk sko sks skt sna snb snd snk snn sno sns snt soa sob sod sok son soo sos sot ss- ssa ssb ssd ssk ssn sso sss sst sta stb std stk stn sto sts stt taa tab tad tak tan tao tas tat tba tbb tbd tbk tbn tbo tbs tbt tda tdb tdd tdk tdn tdo tds tdt tka tkb tkk tko tks tkt tna tnb tnd tnk tnn tno tns tnt to- toa tob tod tok ton too tos tot tsa tsb tsd tsk tsn tso tss tst tta ttb ttd ttk ttn tto tts ttt