-ic a-a a-b a-c a-i a-t aaa aab aac aai aak aas aat ab- aba abb abc abi abk abs abt ac- aca acb acc aci ack acs act ai- aia aib aic aii aik ais ait aka akb akc aki akk aks as- asa asb asc asi ask ass ast at- ata atb atc ati ats att baa bab bac bai bak bas bat bba bbb bbc bbi bbk bbs bbt bca bcb bcc bci bck bcs bct bi- bia bib bic bii bik bis bit bka bkb bkc bkk bks bkt bsa bsb bsc bsi bsk bss bst bta btb btc bti btk bts btt c-- caa cab cac cai cak cas cat cba cbb cbc cbi cbk cbs cbt cca ccb ccc cci cck ccs cct ci- cia cib cic cii cik cis cit cka ckb ckc cki cks ckt csa csb csc csi csk css cst cta ctb ctc cti ctk cts ctt ia- iaa iab iac iai ias iat iba ibb ibc ibi ibk ibs ibt ica icb icc ici ick ics ict iia iib iic iii iis iit ika ikb ikc iki ikk iks ikt is- isa isb isc isi isk iss ist ita itb itc iti itk its itt k-t ka- kaa kab kac kai kak kas kat kba kbb kbc kbi kbk kbs kca kcb kcc kci kck kcs kct kia kib kic kii kik kis kit kkb kkc kki kkk kks kkt ksa ksb ksc ksi ksk kss kst kta ktb ktc ktk kts ktt saa sab sac sai sak sas sat sba sbb sbc sbi sbk sbs sbt sca scb scc sci sck scs sct sia sib sic sii sik sis sit sk- ska skb skc ski skk sks skt ss- ssa ssb ssc ssi ssk sss sst sta stb stc sti stk sts stt taa tab tac tai tak tas tat tba tbb tbc tbi tbk tbs tbt tca tcb tcc tci tck tcs tct tia tib tic tii tik tis tit tka tkb tkc tkk tks tkt tsa tsb tsc tsi tsk tss tst tta ttb ttc tti ttk tts ttt