a-a a-b a-c aaa aab aac aae aah aak aan aas ab- aba abb abc abe abh abk abn abs ac- aca acb acc ace ach ack acn acs aea aeb aec aee aeh aek aen aes aha ahb ahc ahe ahh ahk ahn ahs aka akb akc ake akh akk akn aks an- ana anb anc ane anh ank ann ans as- asa asb asc ase ash ask asn ass baa bab bac bae bah bak ban bas bba bbb bbc bbe bbh bbk bbn bbs bca bcb bcc bce bch bck bcn bcs be- bea beb bec bee beh bek ben bes bha bhb bhc bhe bhh bhk bhs bka bkb bkc bke bkk bkn bks bna bnb bnc bne bnk bnn bns bsa bsb bsc bse bsh bsk bsn bss c-- caa cab cac cae cah cak can cas cba cbb cbc cbe cbh cbk cbn cbs cca ccb ccc cce cch cck ccn ccs ce- cea ceb cec cee ceh cek cen ces ch- cha chb chc che chh chk chn chs cka ckb ckc ckh cks cn- cna cnb cnc cne cnh cnn cns csa csb csc cse csh csk csn css eaa eab eac eae eah eak ean eas eba ebb ebc ebe ebh ebk ebn ebs ec- eca ecb ecc ece ech eck ecn ecs eea eeb eec eee eek een ees eha ehb ehc ehe ehh ehn ehs eka ekb ekc eke ekh eks en- ena enb enc ene enh enk enn ens es- esa esb esc ese esh esk esn ess haa hab hac hae hah hak han has hba hbb hbc hbe hbh hbk hbn hbs hca hcb hcc hce hch hck hcn hcs he- hea heb hec hee heh hek hen hes hha hhb hhc hhe hhh hhk hhn hhs hka hkb hkh hkk hkn hks hna hnb hnc hne hnh hnk hnn hns hsa hsb hsc hse hsh hsk hsn hss ka- kaa kab kac kae kah kak kan kas kba kbb kbc kbe kbh kbk kbn kbs kca kcb kcc kce kch kck kcn kcs ke- kea keb kec kee keh kek ken kes kha khe khh khk khn khs kkb kkc kke kkh kkk kkn kks kn- kna knc kne knk knn ksa ksb ksc kse ksh ksk ksn kss naa nab nac nae nah nak nan nas nba nbb nbc nbe nbk nbn nbs nca ncb ncc nce nch nck ncn ncs ne- nea neb nec nee neh nek nen nes nha nhb nhc nhe nhh nhk nhn nhs nka nkc nke nkk nkn nks nna nnb nnc nne nnh nnk nnn nns nsa nsb nsc nse nsh nsk nsn nss saa sab sac sae sah sak san sas sba sbb sbc sbe sbh sbk sbn sbs sca scb scc sce sch sck scn scs se- sea seb sec see seh sek sen ses sh- sha shb shc she shh shk shn shs sk- ska skb skc ske skh skk sks sna snb snc sne snk snn sns ss- ssa ssb ssc sse ssh ssk ssn sss