-ana aaaa aaab aaac aaan aaas aaba aabb aabc aaca aacb aacc aacn aacs aana aasa aasc aass abaa abab abac aban abas abb- abba abbb abbs abca abcb abcc abcn abcs abs- absa abss acaa acab acac acan acas acba acca accc accs acsa acsc acss ana- anaa anab anac anan anas anba anbb anca ancc anna annb anns ansa asaa asab asac asan asas asba asc- asca ascb ascc asnc assa assc assn asss baaa baan baas baba babb babs bac- baca bacc bacn bacs bana banc bann bans basa basc bass bbas bbbb bbbs bcaa bcas bcbc bcbs bcca bccc bccs bcsa bcsc bcsn bcss bnas bnss bsaa bsac bsas bscs bsns bssc caaa caab caac caan caas caba cabs cac- caca cacc cana canc cann cans casa casb casc cass cbac cbbc cbbs cbca cbcc cbcn cbcs cbna cbsa cbsc cbsn ccaa ccab ccac ccas ccba ccbc ccbn ccca cccb cccc cccs ccna ccnb ccnc ccns ccsa ccsn ccss cnaa cnac cnas cnbc cnna cnsa cnss csaa csab csac csas cscb cscc cscs cssa naaa naab naac naan naas naba nabc nabs naca nacc nacs nan- nana nanb nann nans nas- nasa nasb nasc nass nbaa nbas nbbc nbca nbcc nbcs ncaa ncac ncba ncbc ncbs ncca nccc nccn nccs ncna ncnc ncsa ncsc ncss nnnn nnsa nnss nsaa nsac nsca nscc nscs nsna nssa nssb nssc nsss sa-c saab saac saan saas saba sabb sabc sabs saca sacc sacn sacs sana sann sans sasa sasc sass sbaa sbac sbas sbbs sbca sbcc sbcs sbsa scaa scab scac scan scas scba sccc sccs scna scsa scsc scsn snab snas snba snca sncc snns ssaa ssab ssac ssan ssas ssbn ssca sscc sscs ssns sssa sssb sssc ssss