-al a-a a-b a-i aaa aab aai aal aar aas aax ab- aba abb abi abl abr abs abx ai- aia aib aii ail air ais aix al- ala alb ali all alr als alx ar- ara arb ari arl arr ars arx as- asa asb asi asl asr ass asx ax- axa axi axl axr axs axx baa bab bai bal bar bas bax bba bbb bbi bbl bbr bbs bbx bi- bia bib bii bil bir bis bix bla blb bli bll blr bls blx bra brb bri brl brr brs brx bsa bsb bsi bsl bsr bss bsx bxb bxi bxl bxx ia- iaa iab iai ial iar ias iba ibb ibi ibl ibr ibs ibx iia iib iii iil iir iis iix il- ila ilb ili ill ilr ils ilx ir- ira irb iri irl irr irs irx is- isa isb isi isl isr iss ixi ixl la- laa lab lai lal lar las lax lba lbb lbi lbl lbr lbs lbx lia lib lii lil lir lis lix lla llb lli lll llr lls lra lrb lri lrr lrs lsa lsb lsi lsl lsr lss lxi lxr lxx ra- raa rab rai ral rar ras rax rba rbb rbi rbl rbr rbs rbx ria rib rii ril rir ris rix rla rli rll rlr rls rra rrb rri rrl rrr rrs rsa rsb rsi rsl rsr rss rsx rxr rxs saa sab sai sal sar sas sax sba sbb sbi sbl sbr sbs sbx sia sib sii sil sir sis six sla slb sli sll slr sls slx sr- sra srb sri srl srr srs srx ss- ssa ssb ssi ssl ssr sss ssx sxi sxl sxs xaa xal xar xas xbl xbr xbx xia xii xis xix xla xlb xli xlr xls xrx xsa xsb xsi xsl xss xxi xxl xxx