-al a-a a-c a-t aaa aac aal aat aax ac- aca acc acl act acx al- ala alc all alt alx at- ata atc atl att atx ax- axa axl axt axx c-- caa cac cal cat cax cca ccc ccl cct ccx cl- cla clc cll clt clx cta ctc ctl ctt ctx cxc cxl cxt cxx la- laa lac lal lat lax lca lcc lcl lct lcx lla llc lll llt lta ltc ltl ltt ltx lxc lxx t-x taa tac tal tat tax tca tcc tcl tct tcx tla tlc tll tlt tlx tta ttc ttl ttt ttx txl txt xaa xac xal xat xcl xcx xla xlt xtc xtx xxl xxx