a-a a-b aaa aab aam aan aar aas ab- aba abb abm abn abr abs ama amb amm amn amr ams an- ana anb anm ann anr ans ar- ara arb arm arn arr ars as- asa asb asm asn asr ass baa bab bam ban bar bas bba bbb bbm bbn bbr bbs bma bmb bmm bmn bmr bms bna bnb bnn bnr bns bra brb brm brn brr brs bsa bsb bsm bsn bsr bss m-r maa mab mam man mar mas mba mbb mbm mbr mbs mma mmb mmm mmn mmr mms mna mnb mnm mnn mnr mns mra mrb mrm mrn mrr mrs msa msb msm msn msr mss naa nab nam nan nar nas nba nbb nbm nbn nbr nbs nma nmb nmm nmn nmr nms nna nnb nnm nnn nns nra nrb nrm nrn nrr nrs nsa nsb nsm nsn nsr nss ra- raa rab ram ran rar ras rba rbb rbm rbn rbr rbs rma rmb rmm rmn rmr rms rna rnb rnm rnn rnr rns rra rrb rrm rrn rrr rrs rsa rsb rsm rsn rsr rss saa sab sam san sar sas sba sbb sbm sbn sbr sbs sma smb smm smn smr sms sna snb snm snn snr sns sr- sra srb srm srn srr srs ss- ssa ssb ssm ssn ssr sss