a-a a-b a-c aaa aab aac aae aak aan aao aap aas ab- aba abb abc abe abk abn abo abp abs ac- aca acb acc ace ack acn aco acp acs aea aeb aec aee aek aen aeo aep aes aka akb akc ake akk akn ako akp aks an- ana anb anc ane ank ann ano anp ans aoa aob aoc aoe aok aon aoo aop aos ap- apa apb apc ape apk apn apo app aps as- asa asb asc ase ask asn aso asp ass b-p baa bab bac bae bak ban bao bap bas bba bbb bbc bbe bbk bbn bbo bbp bbs bca bcb bcc bce bck bcn bco bcp bcs be- bea beb bec bee bek ben beo bep bes bka bkb bkc bke bkk bkn bko bkp bks bna bnb bnc bne bnk bnn bno bnp bns boa bob boc boe bok bon boo bop bos bpa bpb bpc bpe bpn bpo bpp bps bsa bsb bsc bse bsk bsn bso bsp bss c-- caa cab cac cae cak can cao cap cas cba cbb cbc cbe cbk cbn cbo cbp cbs cca ccb ccc cce cck ccn cco ccp ccs ce- cea ceb cec cee cek cen ceo cep ces cka ckb ckc cko cks cn- cna cnb cnc cne cnn cno cnp cns co- coa cob coc coe cok con coo cop cos cpa cpb cpc cpe cpk cpn cpo cpp cps csa csb csc cse csk csn cso csp css eaa eab eac eae eak ean eao eap eas eba ebb ebc ebe ebk ebn ebo ebp ebs ec- eca ecb ecc ece eck ecn eco ecs eea eeb eec eee eek een eeo eep ees eka ekb ekc eke eko ekp eks en- ena enb enc ene enk enn eno enp ens eo- eoa eob eoc eoe eok eon eoo eop eos ep- epa epb epc epe epn epo epp eps es- esa esb esc ese esk esn eso esp ess ka- kaa kab kac kae kak kan kao kap kas kba kbb kbc kbe kbk kbn kbo kbp kbs kca kcb kcc kce kck kcn kcp kcs ke- kea keb kec kee kek ken keo kep kes kkb kkc kke kkk kkn kkp kks kn- kna knc kne knk knn kno knp koa kob koc koe kok kon koo kop kos kpa kpc kpe kpk kpn kpo kpp kps ksa ksb ksc kse ksk ksn kso ksp kss naa nab nac nae nak nan nao nap nas nba nbb nbc nbe nbk nbn nbo nbp nbs nca ncb ncc nce nck ncn nco ncp ncs ne- nea neb nec nee nek nen neo nep nes nka nkc nke nkk nkn nko nkp nks nna nnb nnc nne nnk nnn nno nnp nns no- noa nob noc noe nok non noo nop nos npa npb npc npe npn npo npp nps nsa nsb nsc nse nsk nsn nso nsp nss oaa oab oac oae oak oan oao oap oas ob- oba obb obc obe obk obn obo obp obs oc- oca ocb occ ock ocn oco ocp ocs oea oeb oec oee oen oeo oep oes oka okb okc oke okk oko okp oks on- ona onb onc one onk onn ono onp ons oo- ooa oob ooc ook oon ooo oop oos op- opa opb opc ope opk opn opo opp ops os- osa osb osc ose osk osn oso osp oss p-p paa pab pac pae pak pan pao pap pas pba pbb pbc pbe pbk pbn pbo pbp pbs pca pcb pcc pce pck pcn pco pcp pcs pea peb pec pee pek pen peo pep pes pka pkb pkc pke pkn pko pkp pks pn- pna pnb pnc pne pnk pnn pno pnp pns poa pob poc poe pok pon poo pop pos ppa ppb ppc ppe ppk ppn ppo ppp pps ps- psa psb psc pse psk psn pso psp pss saa sab sac sae sak san sao sap sas sba sbb sbc sbe sbk sbn sbo sbp sbs sca scb scc sce sck scn sco scp scs se- sea seb sec see sek sen seo sep ses sk- ska skb skc ske skk sko skp sks sna snb snc sne snk snn sno snp sns soa sob soc soe sok son soo sop sos spa spb spc spe spk spn spo spp sps ss- ssa ssb ssc sse ssk ssn sso ssp sss