-al -er a-a a-b a-c a-t aaa aab aac aae aaf aak aal aar aas aat ab- aba abb abc abe abf abk abl abr abs abt ac- aca acb acc ace acf ack acl acr acs act aea aeb aec aee aef aek ael aer aes aet af- afa afb afc afe aff afk afl afr afs aft aka akb akc ake akk akl akr aks al- ala alb alc ale alf alk all alr als alt ar- ara arb arc are arf ark arl arr ars art as- asa asb asc ase asf ask asl asr ass ast at- ata atb atc ate atf atl atr ats att baa bab bac bae baf bak bal bar bas bat bba bbb bbc bbe bbf bbk bbl bbr bbs bbt bca bcb bcc bce bcf bck bcl bcr bcs bct be- bea beb bec bee bef bek bel ber bes bet bfa bfb bfc bfe bff bfl bfr bfs bft bka bkb bkc bke bkf bkk bkl bkr bks bkt bla blb blc ble blf blk bll blr bls blt bra brb bre brf brk brl brr brs brt bsa bsb bsc bse bsf bsk bsl bsr bss bst bta btb btc bte btf btk btl btr bts btt c-- caa cab cac cae caf cak cal car cas cat cba cbb cbc cbe cbf cbk cbl cbr cbs cbt cca ccb ccc cce ccf cck ccl ccr ccs cct ce- cea ceb cec cee cef cek cel cer ces cet cfa cfb cfc cfe cff cfk cfl cfr cfs cft cka ckb ckc cks ckt cl- cla clb clc cle clf clk cll clr cls clt cra crb crc cre crf crk crl crr crs crt csa csb csc cse csf csk csl csr css cst cta ctb ctc cte ctf ctk ctl ctr cts ctt eaa eab eac eae eaf eak eal ear eas eat eba ebb ebc ebe ebf ebk ebl ebr ebs ebt ec- eca ecb ecc ece ecf eck ecl ecr ecs ect eea eeb eec eee eef eek eel eer ees eet ef- efa efb efc efe eff efl efr efs eft eka ekb ekc eke ekf ekl ekr eks ekt ela elb elc ele elf elk ell elr els elt era erb erc ere erf erk erl err ers ert es- esa esb esc ese esf esk esl esr ess est eta etb etc ete etf etk etl etr ets ett faa fab fac fae faf fak fal far fas fat fba fbb fbc fbe fbf fbk fbl fbr fbs fbt fca fcb fcc fce fcf fck fcl fcr fcs fct fea feb fec fee fef fek fel fer fes fet ffa ffc ffe fff ffk ffl ffr ffs fft fka fkb fkc fkf fkk fkl fkt fla flb flc fle flf fll flr fls flt fra frb frc fre frf frk frl frr frs frt fsa fsb fsc fse fsf fsk fsl fsr fss fst fta ftb ftc fte ftf ftk ftl ftr fts ftt k-t ka- kaa kab kac kae kaf kak kal kar kas kat kba kbb kbc kbe kbf kbk kbl kbr kbs kca kcb kcc kce kck kcl kcr kcs kct ke- kea keb kec kee kef kek kel ker kes ket kfa kfc kff kfs kkb kkc kke kkk kkl kkr kks kkt kl- kla klb klc klf klr kls klt kra krc krf krk krl krr krs krt ksa ksb ksc kse ksf ksk ksl ksr kss kst kta ktb ktc kte ktf ktk ktl ktr kts ktt la- laa lab lac lae laf lak lal lar las lat lba lbb lbc lbe lbf lbk lbl lbr lbs lbt lca lcb lcc lce lcf lck lcl lcr lcs lct lea leb lec lee lef lek lel ler les let lfa lfb lfc lfe lff lfk lfl lfr lfs lft lka lkb lkl lkr lks lkt lla llb llc lle llf llk lll llr lls llt lra lrb lrc lrf lrk lrr lrs lrt lsa lsb lsc lse lsf lsk lsl lsr lss lst lta ltb ltc lte ltf ltk ltl ltr lts ltt ra- raa rab rac rae raf rak ral rar ras rat rba rbb rbc rbe rbf rbk rbl rbr rbs rbt rca rcb rcc rce rcf rcl rcr rcs rct re- rea reb rec ree ref rek rel rer res ret rfa rfb rfc rfe rff rfk rfl rfr rfs rft rkb rkc rke rkf rkk rks rkt rla rlc rle rlf rll rlr rls rlt rra rrb rrc rrf rrk rrl rrr rrs rrt rsa rsb rsc rse rsf rsk rsl rsr rss rst rta rtb rtc rte rtf rtk rtl rtr rts rtt saa sab sac sae saf sak sal sar sas sat sba sbb sbc sbe sbf sbk sbl sbr sbs sbt sca scb scc sce scf sck scl scr scs sct se- sea seb sec see sef sek sel ser ses set sfa sfb sfc sfe sff sfk sfl sfr sfs sft sk- ska skb skc ske skf skk skl skr sks skt sla slb slc sle slf slk sll slr sls slt sr- sra srb src sre srf srk srl srr srs srt ss- ssa ssb ssc sse ssf ssk ssl ssr sss sst sta stb stc ste stf stk stl str sts stt taa tab tac tae taf tak tal tar tas tat tba tbb tbc tbe tbf tbk tbl tbr tbs tbt tca tcb tcc tce tcf tck tcl tcr tcs tct te- tea teb tec tee tef tek tel ter tes tet tfa tfb tfc tfe tff tfk tfl tfr tfs tft tka tkb tkc tke tkk tkl tkr tks tkt tla tlc tle tlf tlk tll tlr tls tlt tra trb trc tre trf trk trl trr trs trt tsa tsb tsc tse tsf tsk tsl tsr tss tst tta ttb ttc tte ttf ttk ttl ttr tts ttt

-ase a-ak a-be aaaa aaab aaac aaae aaaf aaal aaar aaas aaba aabb aabc aabl