-al a-a a-b a-c aaa aab aac aag aak aal aas ab- aba abb abc abg abk abl abs ac- aca acb acc acg ack acl acs ag- aga agb agc agg agk agl ags aka akb akc akg akk akl aks al- ala alb alc alg alk all als as- asa asb asc asg ask asl ass baa bab bac bag bak bal bas bba bbb bbc bbg bbk bbl bbs bca bcb bcc bcg bck bcl bcs bga bgb bgc bgg bgk bgl bgs bka bkb bkc bkg bkk bkl bks bla blb blc blg blk bll bls bsa bsb bsc bsg bsk bsl bss c-- caa cab cac cag cak cal cas cba cbb cbc cbg cbk cbl cbs cca ccb ccc ccg cck ccl ccs cga cgb cgc cgg cgl cgs cka ckb ckc cks cl- cla clb clc clg clk cll cls csa csb csc csg csk csl css gaa gab gac gag gak gal gas gba gbc gbg gbk gbl gbs gca gcb gcc gcg gck gcl gcs gga ggb ggc ggg ggs gka gkb gks gla glb glc glg glk gll gls gsa gsb gsc gsg gsk gsl gss ka- kaa kab kac kag kak kal kas kba kbb kbc kbk kbl kbs kca kcb kcc kcg kck kcl kcs kga kgb kgc kgl kgs kkb kkc kkk kkl kks kl- kla klb klc klg kls ksa ksb ksc ksg ksk ksl kss la- laa lab lac lag lak lal las lba lbb lbc lbg lbk lbl lbs lca lcb lcc lcg lck lcl lcs lga lgb lgc lgg lgk lgl lgs lka lkb lkg lkl lks lla llb llc llg llk lll lls lsa lsb lsc lsg lsk lsl lss saa sab sac sag sak sal sas sba sbb sbc sbg sbk sbl sbs sca scb scc scg sck scl scs sga sgb sgc sgg sgk sgl sgs sk- ska skb skc skg skk skl sks sla slb slc slg slk sll sls ss- ssa ssb ssc ssg ssk ssl sss