a-a a-c a-t aaa aac aae aak aas aat ac- aca acc ace ack acs act aea aec aee aek aes aet aka akc ake akk aks as- asa asc ase ask ass ast at- ata atc ate ats att c-- caa cac cae cak cas cat cca ccc cce cck ccs cct ce- cea cec cee cek ces cet cka ckc cks ckt csa csc cse csk css cst cta ctc cte ctk cts ctt eaa eac eae eak eas eat ec- eca ecc ece eck ecs ect eea eec eee eek ees eet eka ekc eke eks ekt es- esa esc ese esk ess est eta etc ete etk ets ett k-t ka- kaa kac kae kak kas kat kca kcc kce kck kcs kct ke- kea kec kee kek kes ket kkc kke kkk kks kkt ksa ksc kse ksk kss kst kta ktc kte ktk kts ktt saa sac sae sak sas sat sca scc sce sck scs sct se- sea sec see sek ses set sk- ska skc ske skk sks skt ss- ssa ssc sse ssk sss sst sta stc ste stk sts stt taa tac tae tak tas tat tca tcc tce tck tcs tct te- tea tec tee tek tes tet tka tkc tke tkk tks tkt tsa tsc tse tsk tss tst tta ttc tte ttk tts ttt