a-a a-b a-c aaa aab aac aak aan aar aas ab- aba abb abc abk abn abr abs ac- aca acb acc ack acn acr acs aka akb akc akk akn akr aks an- ana anb anc ank ann anr ans ar- ara arb arc ark arn arr ars as- asa asb asc ask asn asr ass baa bab bac bak ban bar bas bba bbb bbc bbk bbn bbr bbs bca bcb bcc bck bcn bcr bcs bka bkb bkc bkk bkn bkr bks bna bnb bnc bnk bnn bnr bns bra brb brk brn brr brs bsa bsb bsc bsk bsn bsr bss c-- caa cab cac cak can car cas cba cbb cbc cbk cbn cbr cbs cca ccb ccc cck ccn ccr ccs cka ckb ckc cks cn- cna cnb cnc cnn cnr cns cra crb crc crk crn crr crs csa csb csc csk csn csr css ka- kaa kab kac kak kan kar kas kba kbb kbc kbk kbn kbr kbs kca kcb kcc kck kcn kcr kcs kkb kkc kkk kkn kkr kks kn- kna knc knk knn knr kra krc krk krn krr krs ksa ksb ksc ksk ksn ksr kss naa nab nac nak nan nar nas nba nbb nbc nbk nbn nbr nbs nca ncb ncc nck ncn ncr ncs nka nkc nkk nkn nkr nks nna nnb nnc nnk nnn nns nra nrb nrc nrk nrn nrr nrs nsa nsb nsc nsk nsn nsr nss ra- raa rab rac rak ran rar ras rba rbb rbc rbk rbn rbr rbs rca rcb rcc rcn rcr rcs rkb rkc rkk rks rna rnb rnc rnn rnr rns rra rrb rrc rrk rrn rrr rrs rsa rsb rsc rsk rsn rsr rss saa sab sac sak san sar sas sba sbb sbc sbk sbn sbr sbs sca scb scc sck scn scr scs sk- ska skb skc skk skr sks sna snb snc snk snn snr sns sr- sra srb src srk srn srr srs ss- ssa ssb ssc ssk ssn ssr sss

-ana a-ak aaaa aaab aaac aaan aaar aaas aaba aabb aabc aaca aacb aacc aack aacn aacr aacs aaka aana aara aarc aars aasa aasc aass abaa abab abac abak aban abar abas abb- abba abbb abbr abbs abca abcb abcc abcn abcr abcs abra abrc abrs abs- absa abss acaa acab acac acan acar acas acba acca accc accs acks acr- acra acrc acrr acrs acsa acsc acss akaa akan akar akas akca akka akna akr- akra aksa ana- anaa anab anac anak anan anar anas anba anbb anca ancc ank- anka anna annb anns anrc ansa arab arac arak aran arar aras arba arbs arc- arca arcs arka arks arna arnk arns arr- arra arrc arrk arrr arrs ars- arsa arsc arsk asaa asab asac asak asan asar asas asba asc- asca ascb ascc ascr aska askr asks asnc asra asrc asrs assa assc assk assn assr asss baaa baak baan baar baas baba babb babr babs bac- baca bacc back bacn bacs bak- baka bakr baks bana banc bank bann banr bans bar- bara barb barc bark barn barr bars basa basc bask bass bbas bbbb bbbs bbrc bcaa bcar bcas bcbc bcbs bcca bccc bccs bcra bcrs bcsa bcsc bcsn bcss bnas bnrr bnss brab brac brak bran bras brca brcb brka brkb brna brns brrr brrs brsb brsr bsaa bsac bsas bscs bsns bsra bssc caaa caab caac caan caas caba cabs cac- caca cacc cack cacr caka cana canc cank cann cans cara carb carc cark carn carr cars casa casb casc cask casr cass cbac cbar cbbc cbbs cbca cbcc cbcn cbcr cbcs cbka cbkn cbkr cbna cbrn cbsa cbsc cbsn ccaa ccab ccac ccar ccas ccba ccbc ccbn ccca cccb cccc cccs ccna ccnb ccnc ccnr ccns ccra ccrc ccrs ccsa ccsn ccss ckac ckan ckbc ckck ckcs cknb cknc ckns ckrc cksa cksb cnaa cnac cnas cnbc cnna cnrc cnrr cnsa cnss crab crac cran crar cras crbc crca crcc crcr crkc crna crns crsa crss csaa csab csac csak csar csas cscb cscc cscr cscs cska csks csra csrc csrs cssa cssr kaaa kaab kaak kaan kaar kaas kaba kabb kabc kabr kacb kacc kacs kaka kakc kakk kakn kaks kana kanb kann kans kara karb kark karn karr kars kas- kasa kasb kasc kask kasn kasr kass kbaa kbab kbac kbak kbar kbas kbba kbbb kbbc kbbk kbbr kbbs kbca kbcb kbck kbcr kbcs kbkb kbkk kbkr kbna kbnn kbnr kbra kbrb kbrc kbrk kbrn kbsa kbsb kbsk kbsn kbsr kbss kcaa kcab kcac kcar kcas kcba kcbc kcbk kcbr kcbs kcca kccb kccc kcck kccr kckc kckk kckn kckr kcnb kcnr kcns kcrc kcrn kcrr kcrs kcsa kcsb kcsc kcsn kcsr kcss kkaa kkac kkan kkar kkba kkbb kkbn kkbr kkbs kkcb kkck kkcn kkcr kkcs kkkk kknb kknn kkns kkrb kkrc kkrk kkrn kkrr kkrs kksa kksn kksr kkss knaa knab knac knan knar knas knba knbb knbc knbn knbr knca kncb knck kncn kncr knkk knnb knnk knnr knns knrb knrk knrs knsa knsb knsc knsk knsn knsr knss krab krac krak kran krar kras krba krbb krbk krbr krca krcb krcc krcn krcs krka krkc krkk krkn krkr krks krna krnb krnk krnn krrb krrc krrk krrn krrr krrs krsa krsc krsk krsn krsr krss ksab ksac ksak ksan ksar ksas ksba ksbc ksbn ksbr ksbs ksca kscb ksck kscn kscr kscs kska kskb kskk kskn kskr ksks ksna ksnb ksnc ksnk ksnn ksnr ksns ksra ksrb ksrn ksrr ksrs kssa kssn kssr ksss naaa naab naac naan naar naas naba nabc nabk nabs naca nacc nack nacs naka naks nan- nana nanb nann nans nara narc nark narn narr nars nas- nasa nasb nasc nask nasr nass nbaa nbak nbar nbas nbbc nbca nbcc nbcs ncaa ncac ncar ncba ncbc ncbs ncca nccc nccn nccr nccs ncna ncnc ncra ncrc ncsa ncsc ncss nnnn nnsa nnss nrab nras nrca nrcs nrna nrrc