-ana aaaa aaab aaac aaan aaba aabb aabc aaca aacb aacc aacn aaco aana aaon aaoo abaa abab abac aban abb- abba abbb abbo abca abcb abcc abcn aboa abob abon aboo acaa acab acac acan acba acca accc acco acoa acon ana- anaa anab anac anan anao anba anbb anbo anca ancc anco anna annb anno ano- anoa anon aoba aoca aonb aono baaa baan baba babb babo bac- baca bacc bacn baco bana banc bann bano baon bbbb bcaa bcbc bcca bccc bnoc boab boac boan boba bobb bobo boca boco bona bonc bonn bono boob booc boon c-bo caaa caab caac caan caba cabo cac- caca cacc caco cana canc cann cano cbac cbbc cbca cbcc cbcn cbna ccaa ccab ccac ccba ccbc ccbn ccca cccb cccc ccna ccnb ccnc ccob ccoc cnaa cnac cnbc cnco cnna coan coba cobb cobo coca coco con- cona conc conn cono coob coon naaa naab naac naan naba nabc nabo naca nacc naco nan- nana nanb nann nano naoc nbaa nbbc nbbo nbca nbcc nbco ncaa ncac ncba ncbc ncca nccc nccn ncna ncnc ncoa ncoc nnnn noaa noac noba nobc nobo noco non- nona nonn nono noo- noob noon nooo oban obba obbo obon ocab ocac ocan ocbc occa occc occn ocna ocon onab onan onc- onca onco onna onno onon ooaa ooba oona oooo