a-a a-c aaa aac aao aar aas aax aay ac- aca acc aco acr acs acx acy aoa aoc aoo aor aos aox ar- ara arc aro arr ars arx ary as- asa asc aso asr ass asx asy ax- axa axo axr axs axx ay- aya ayc ayo ayr ays ayx c-- caa cac cao car cas cax cay cca ccc cco ccr ccs ccx co- coa coc coo cor cos cox coy cra crc cro crr crs crx cry csa csc cso csr css csx csy cxc cxo cxr cxs cxx cya cyc cyo cyr cys oaa oac oao oar oas oax oc- oca occ oco ocr ocs ocx oo- ooa ooc ooo oor oos oox or- ora orc oro orr ors orx ory os- osa osc oso osr oss osx ox- oxa oxc oxo oxx oxy oya oyo oys ra- raa rac rao rar ras rax ray rca rcc rco rcr rcs rcx roa roc roo ror ros rox roy rra rrc rrr rrs rsa rsc rso rsr rss rsx rxr rxs ry- rya ryc ryo ryr rys ryy saa sac sao sar sas sax say sca scc sco scr scs scx soa soc soo sor sos sox soy sr- sra src sro srr srs srx sry ss- ssa ssc sso ssr sss ssx sxc sxs sy- sya syc syr sys syx xaa xac xar xas xcr xcx xoa xoc xoo xor xos xox xrc xrx xry xsa xsc xss xxo xxx xxy xyr xyy yaa yac yao yar yas yax yay yca ycc yco ycs ycy yoc yoo yor yos yox yoy yra yrc yro yrs ysa ysc yso ysr yss ysy yxa yxy yyc yys yyy