-al a-a a-b a-c a-t aaa aab aac aae aal aas aat ab- aba abb abc abe abl abs abt ac- aca acb acc ace acl acs act aea aeb aec aee ael aes aet al- ala alb alc ale all als alt as- asa asb asc ase asl ass ast at- ata atb atc ate atl ats att baa bab bac bae bal bas bat bba bbb bbc bbe bbl bbs bbt bca bcb bcc bce bcl bcs bct be- bea beb bec bee bel bes bet bla blb blc ble bll bls blt bsa bsb bsc bse bsl bss bst bta btb btc bte btl bts btt c-- caa cab cac cae cal cas cat cba cbb cbc cbe cbl cbs cbt cca ccb ccc cce ccl ccs cct ce- cea ceb cec cee cel ces cet cl- cla clb clc cle cll cls clt csa csb csc cse csl css cst cta ctb ctc cte ctl cts ctt eaa eab eac eae eal eas eat eba ebb ebc ebe ebl ebs ebt ec- eca ecb ecc ece ecl ecs ect eea eeb eec eee eel ees eet ela elb elc ele ell els elt es- esa esb esc ese esl ess est eta etb etc ete etl ets ett la- laa lab lac lae lal las lat lba lbb lbc lbe lbl lbs lbt lca lcb lcc lce lcl lcs lct lea leb lec lee lel les let lla llb llc lle lll lls llt lsa lsb lsc lse lsl lss lst lta ltb ltc lte ltl lts ltt saa sab sac sae sal sas sat sba sbb sbc sbe sbl sbs sbt sca scb scc sce scl scs sct se- sea seb sec see sel ses set sla slb slc sle sll sls slt ss- ssa ssb ssc sse ssl sss sst sta stb stc ste stl sts stt taa tab tac tae tal tas tat tba tbb tbc tbe tbl tbs tbt tca tcb tcc tce tcl tcs tct te- tea teb tec tee tel tes tet tla tlc tle tll tls tlt tsa tsb tsc tse tsl tss tst tta ttb ttc tte ttl tts ttt