-er a-a a-b a-q aaa aab aae aao aaq aar aas ab- aba abb abe abo abq abr abs aea aeb aee aeo aeq aer aes aoa aob aoe aoo aor aos aqa aqo aqr aqs ar- ara arb are aro arq arr ars as- asa asb ase aso asq asr ass baa bab bae bao baq bar bas bba bbb bbe bbo bbq bbr bbs be- bea beb bee beo beq ber bes boa bob boe boo boq bor bos bqe bra brb bre bro brq brr brs bsa bsb bse bso bsr bss eaa eab eae eao ear eas eba ebb ebe ebo ebq ebr ebs eea eeb eee eeo eer ees eo- eoa eob eoe eoo eoq eor eos eqa eqe eqq eqs era erb ere ero erq err ers es- esa esb ese eso esq esr ess oaa oab oae oao oaq oar oas ob- oba obb obe obo obr obs oea oeb oee oeo oer oes oo- ooa oob ooo oor oos oqb oqo or- ora orb ore oro orr ors os- osa osb ose oso osq osr oss qaa qar qas qba qbe qbq qbs qee qeo qoo qor qos qqq qra qrb qre qrs qsa qso qsr ra- raa rab rae rao raq rar ras rba rbb rbe rbo rbr rbs re- rea reb ree reo req rer res roa rob roe roo ror ros rqs rra rrb rrq rrr rrs rsa rsb rse rso rsq rsr rss saa sab sae sao saq sar sas sba sbb sbe sbo sbq sbr sbs se- sea seb see seo seq ser ses soa sob soe soo soq sor sos sqa sqq sqr sqs sr- sra srb sre sro srq srr srs ss- ssa ssb sse sso ssq ssr sss