-al -er a-a a-b a-c aaa aab aac aae aak aal aap aar ab- aba abb abc abe abk abl abp abr ac- aca acb acc ace ack acl acp acr aea aeb aec aee aek ael aep aer aka akb akc ake akk akl akp akr al- ala alb alc ale alk all alp alr ap- apa apb apc ape apk apl app apr ar- ara arb arc are ark arl arp arr b-p baa bab bac bae bak bal bap bar bba bbb bbc bbe bbk bbl bbp bbr bca bcb bcc bce bck bcl bcp bcr be- bea beb bec bee bek bel bep ber bka bkb bkc bke bkk bkl bkp bkr bla blb blc ble blk bll blp blr bpa bpb bpc bpe bpl bpp bpr bra brb bre brk brl brp brr c-- caa cab cac cae cak cal cap car cba cbb cbc cbe cbk cbl cbp cbr cca ccb ccc cce cck ccl ccp ccr ce- cea ceb cec cee cek cel cep cer cka ckb ckc cl- cla clb clc cle clk cll clp clr cpa cpb cpc cpe cpk cpl cpp cpr cra crb crc cre crk crl crp crr eaa eab eac eae eak eal eap ear eba ebb ebc ebe ebk ebl ebp ebr ec- eca ecb ecc ece eck ecl ecr eea eeb eec eee eek eel eep eer eka ekb ekc eke ekl ekp ekr ela elb elc ele elk ell elp elr ep- epa epb epc epe epl epp epr era erb erc ere erk erl erp err ka- kaa kab kac kae kak kal kap kar kba kbb kbc kbe kbk kbl kbp kbr kca kcb kcc kce kck kcl kcp kcr ke- kea keb kec kee kek kel kep ker kkb kkc kke kkk kkl kkp kkr kl- kla klb klc klr kpa kpc kpe kpk kpl kpp kpr kra krc krk krl krp krr l-p la- laa lab lac lae lak lal lap lar lba lbb lbc lbe lbk lbl lbp lbr lca lcb lcc lce lck lcl lcp lcr lea leb lec lee lek lel lep ler lka lkb lkl lkp lkr lla llb llc lle llk lll llp llr lpa lpb lpc lpe lpk lpl lpp lpr lra lrb lrc lrk lrp lrr p-p paa pab pac pae pak pal pap par pba pbb pbc pbe pbk pbl pbp pbr pca pcb pcc pce pck pcl pcp pcr pea peb pec pee pek pel pep per pka pkb pkc pke pkl pkp pkr pla plb plc ple plk pll plp plr ppa ppb ppc ppe ppk ppl ppp ppr pra prb prc pre prk prl prp prr ra- raa rab rac rae rak ral rap rar rba rbb rbc rbe rbk rbl rbp rbr rca rcb rcc rce rcl rcp rcr re- rea reb rec ree rek rel rep rer rkb rkc rke rkk rkp rla rlc rle rll rlp rlr rpa rpb rpc rpe rpk rpl rpp rpr rra rrb rrc rrk rrl rrp rrr