-ic bbb bbc bbi bbm bbo bbr bbs bcb bcc bci bcm bco bcr bcs bi- bib bic bii bim bio bir bis bmb bmc bmi bmm bmo bmr bms bob boc boi bom boo bor bos brb bri brm bro brr brs bsb bsc bsi bsm bso bsr bss c-- cbb cbc cbi cbm cbo cbr cbs ccb ccc cci ccm cco ccr ccs ci- cib cic cii cim cio cir cis cmb cmc cmi cmm cmo cmr cms co- cob coc coi com coo cor cos crb crc cri crm cro crr crs csb csc csi csm cso csr css ibb ibc ibi ibm ibo ibr ibs icb icc ici icm ico icr ics iib iic iii iim iio iir iis im- imb imc imi imm imo ims io- iob ioc ioi iom ioo ior ios ir- irb irc iri irm iro irr irs is- isb isc isi ism iso isr iss m-o m-r mbb mbc mbi mbm mbo mbr mbs mc- mcb mcc mci mcm mco mcr mcs mi- mib mic mii mim mio mir mis mmb mmc mmi mmm mmo mmr mms mob moc moi mom moo mor mos mrb mrc mri mrm mro mrr mrs msb msc msi msm mso msr mss o-i ob- obb obc obi obm obo obr obs oc- ocb occ oci ocm oco ocr ocs oib oic oii oim oio oir ois om- omb omc omi omm omo omr oms oo- oob ooc ooi oom ooo oor oos or- orb orc ori orm oro orr ors os- osb osc osi osm oso osr oss rbb rbc rbi rbm rbo rbr rbs rcb rcc rci rcm rco rcr rcs rib ric rii rim rio rir ris rmb rmc rmi rmm rmo rmr rms rob roc roi rom roo ror ros rrb rrc rri rrm rrr rrs rsb rsc rsi rsm rso rsr rss sbb sbc sbi sbm sbo sbr sbs scb scc sci scm sco scr scs sib sic sii sim sio sir sis smb smc smi smm smo smr sms sob soc soi som soo sor sos sr- srb src sri srm sro srr srs ss- ssb ssc ssi ssm sso ssr sss