-ana aaaa aaab aaac aaaf aaan aaba aabb aabc aaca aacb aacc aacf aacn aaco aafa aafb aafc aaff aana aaon aaoo abaa abab abac abaf aban abb- abba abbb abbo abca abcb abcc abcf abcn abff aboa abob abof abon aboo acaa acab acac acan acba acca accc accf acco acfc acoa acon afaa afan afao afca afcb afcc affa affc affo afoa afoo ana- anaa anab anac anan anao anba anbb anbo anca ancc anco anfa anfo anna annb anno ano- anoa anon aoba aoca aonb aono baaa baaf baan baba babb babo bac- baca bacc bacn baco bafc baff bafo bana banc bann bano baon bbbb bbfc bbfn bcaa bcbc bcca bccc bcfc bcof bfca bnoc boab boac boan boba bobb bobo boca boco bofa boff bona bonc bonn bono boob booc boof boon c-bo caaa caab caac caaf caan caba cabf cabo cac- caca cacc caco cafa cafb cafc caff cana canc cann cano cbac cbbc cbca cbcc cbcn cbfb cbfc cbna ccaa ccab ccac ccaf ccba ccbc ccbn ccca cccb cccc cccf ccfa ccfc ccff ccna ccnb ccnc ccnf ccob ccoc cfaa cfab cfac cfao cfbc cfbn cfca cfcb cfcf cfcn cfco cffb cfnb cfoa cnaa cnac cnbc cnco cnfa cnna coan coba cobb cobo coca coco cofc coff con- cona conc conf conn cono coob coof coon faaa faac faan faba fabo faca facc fafa fafc faff fafo fana fanc fano faon fcab fcba fcca fccf ffcc ffff fnac foaf foan foba foca foco fofo fono foof foon naaa naab naac naan naba nabc nabf nabo naca nacc nacf naco nafa nafc naff nafo nan- nana nanb nann nano naoc nbaa nbaf nbbc nbbo nbca nbcc nbco nbfa nbfc ncaa ncac ncba ncbc ncca nccc nccf nccn ncfc ncna ncnc ncoa ncoc nfaa nfff nfon nnnn noaa noac noba nobc nobo noco non- nona nonn nono noo- noob noon nooo oafc oafo oban obba obbo obon ocab ocac ocan ocbc occa occc occn ocfa ocna ocon ofan off- offa offc offo ofna ofno onab onan onc- onca oncf onco onna onno onon ooaa ooba ooff oona oooo