-ic a-a a-b a-c a-i aaa aab aac aaf aai aak aao aar aas ab- aba abb abc abf abi abk abo abr abs ac- aca acb acc acf aci ack aco acr acs af- afa afb afc aff afi afk afo afr afs ai- aia aib aic aif aii aik aio air ais aka akb akc aki akk ako akr aks aoa aob aoc aof aoi aok aoo aor aos ar- ara arb arc arf ari ark aro arr ars as- asa asb asc asf asi ask aso asr ass baa bab bac baf bai bak bao bar bas bba bbb bbc bbf bbi bbk bbo bbr bbs bca bcb bcc bcf bci bck bco bcr bcs bfa bfb bfc bff bfi bfo bfr bfs bi- bia bib bic bif bii bik bio bir bis bka bkb bkc bkf bkk bko bkr bks boa bob boc bof boi bok boo bor bos bra brb brf bri brk bro brr brs bsa bsb bsc bsf bsi bsk bso bsr bss c-- caa cab cac caf cai cak cao car cas cba cbb cbc cbf cbi cbk cbo cbr cbs cca ccb ccc ccf cci cck cco ccr ccs cfa cfb cfc cff cfi cfk cfo cfr cfs ci- cia cib cic cif cii cik cio cir cis cka ckb ckc cki cko cks co- coa cob coc cof coi cok coo cor cos cra crb crc crf cri crk cro crr crs csa csb csc csf csi csk cso csr css faa fab fac faf fai fak fao far fas fba fbb fbc fbf fbi fbk fbo fbr fbs fca fcb fcc fcf fci fck fco fcr fcs ffa ffc fff ffi ffk ffo ffr ffs fia fib fic fif fii fik fir fis fka fkb fkc fkf fki fkk foa fob foc fof foi fok foo for fos fra frb frc frf fri frk fro frr frs fsa fsb fsc fsf fsi fsk fso fsr fss i-f ia- iaa iab iac iaf iai iao iar ias iba ibb ibc ibf ibi ibk ibo ibr ibs ica icb icc icf ici ick ico icr ics ifa ifb ifc iff ifi ifo ifr ifs iia iib iic iif iii iio iir iis ika ikb ikc ikf iki ikk iko ikr iks io- ioa iob ioc iof ioi ioo ior ios ir- ira irb irc irf iri irk iro irr irs is- isa isb isc isf isi isk iso isr iss ka- kaa kab kac kaf kai kak kao kar kas kba kbb kbc kbf kbi kbk kbo kbr kbs kca kcb kcc kci kck kcr kcs kfa kfc kff kfi kfo kfs kia kib kic kif kii kik kio kir kis kkb kkc kki kkk kkr kks koa kob koc kof koi kok koo kor kos kra krc krf kri krk kro krr krs ksa ksb ksc ksf ksi ksk kso ksr kss o-i oaa oab oac oaf oai oak oao oar oas ob- oba obb obc obf obi obk obo obr obs oc- oca ocb occ ocf oci ock oco ocr ocs of- ofa ofb ofc off ofi ofo ofr ofs oia oib oic oif oii oik oio oir ois oka okb okc oki okk oko okr oks oo- ooa oob ooc oof ooi ook ooo oor oos or- ora orb orc orf ori ork oro orr ors os- osa osb osc osf osi osk oso osr oss ra- raa rab rac raf rai rak rao rar ras rba rbb rbc rbf rbi rbk rbo rbr rbs rca rcb rcc rcf rci rco rcr rcs rfa rfb rfc rff rfi rfk rfo rfr rfs ria rib ric rif rii rik rio rir ris rkb rkc rkf rkk rko rks roa rob roc rof roi rok roo ror ros rra rrb rrc rrf rri rrk rrr rrs rsa rsb rsc rsf rsi rsk rso rsr rss saa sab sac saf sai sak sao sar sas sba sbb sbc sbf sbi sbk sbo sbr sbs sca scb scc scf sci sck sco scr scs sfa sfb sfc sff sfi sfk sfo sfr sfs sia sib sic sif sii sik sio sir sis sk- ska skb skc skf ski skk sko skr sks soa sob soc sof soi sok soo sor sos sr- sra srb src srf sri srk sro srr srs ss- ssa ssb ssc ssf ssi ssk sso ssr sss

a-ak a-ii a-ok aaaa aaab aaac aaaf aaai aaar aaas aaba aabb aabc aabi aaca aacb aacc aacf aaci aack aaco aacr aacs aafa aafb aafc aaff aafi aaib aaic aaii aais aaka aaoo aara aarc aari aaro aars aasa aasc aasf aasi aass abaa abab abac abaf abai abak abar abas abb- abba abbb abbi abbo abbr abbs abca abcb abcc abcf abci abcr abcs abff abia abib abic abir abis aboa abob abof abok aboo abor abos abra abrc abri abro abrs abs- absa absf absi abss acaa acab acac acai acar acas acba acca accc accf acci acco accs acfc acfi acfs aci- acia acic acif acir acis acks acoa acor acos acr- acra acrc acri acro acrr acrs acsa acsc acsi acss afaa afak afao afar afbs afca afcb afcc afci afcs affa affc affi affo affs afia afib afif afik afir afis afka afkr afoa afoo afor afr- afra afrc afri afro afrs afsa afsb afsc aiai aias aiba aibo aica aicc aicf aicr aics aiff aifs aiia aiib aiic aiir aika aiki aiko aiks aioc aioi aira airi airo airs aisa aisb aisi aisk aiso aisr akaa akai akao akar akas akca akia akif akik akio akir akis akka akki akko akok akos akr- akra aksa aksi aoba aoca aocs aoki aoks aora aorb aors aoss arab arac araf arai arak arar aras arba arbi arbs arc- arca arci arco arcs arfa arfb arfc arff arfs aria arib arif arii arik ario aris arka arki arko arks aroa arob aroi aroo aror aros arr- arra arrc arri arrk arro arrr arrs ars- arsa arsc arsi