-al a-a a-b a-c a-t aaa aab aac aae aal aat ab- aba abb abc abe abl abt ac- aca acb acc ace acl act aea aeb aec aee ael aet al- ala alb alc ale all alt at- ata atb atc ate atl att baa bab bac bae bal bat bba bbb bbc bbe bbl bbt bca bcb bcc bce bcl bct be- bea beb bec bee bel bet bla blb blc ble bll blt bta btb btc bte btl btt c-- caa cab cac cae cal cat cba cbb cbc cbe cbl cbt cca ccb ccc cce ccl cct ce- cea ceb cec cee cel cet cl- cla clb clc cle cll clt cta ctb ctc cte ctl ctt eaa eab eac eae eal eat eba ebb ebc ebe ebl ebt ec- eca ecb ecc ece ecl ect eea eeb eec eee eel eet ela elb elc ele ell elt eta etb etc ete etl ett la- laa lab lac lae lal lat lba lbb lbc lbe lbl lbt lca lcb lcc lce lcl lct lea leb lec lee lel let lla llb llc lle lll llt lta ltb ltc lte ltl ltt taa tab tac tae tal tat tba tbb tbc tbe tbl tbt tca tcb tcc tce tcl tct te- tea teb tec tee tel tet tla tlc tle tll tlt tta ttb ttc tte ttl ttt