-ic bbb bbc bbi bbn bbo bbr bbs bcb bcc bci bcn bco bcr bcs bi- bib bic bii bin bio bir bis bnb bnc bni bnn bno bnr bns bob boc boi bon boo bor bos brb bri brn bro brr brs bsb bsc bsi bsn bso bsr bss c-- cbb cbc cbi cbn cbo cbr cbs ccb ccc cci ccn cco ccr ccs ci- cib cic cii cin cio cir cis cn- cnb cnc cni cnn cno cnr cns co- cob coc coi con coo cor cos crb crc cri crn cro crr crs csb csc csi csn cso csr css ibb ibc ibi ibn ibo ibr ibs icb icc ici icn ico icr ics iib iic iii iin iio iir iis in- inb inc ini inn ino inr ins io- iob ioc ioi ion ioo ior ios ir- irb irc iri irn iro irr irs is- isb isc isi isn iso isr iss n-i nbb nbc nbi nbn nbo nbr nbs ncb ncc nci ncn nco ncr ncs nib nic nii nin nio nir nis nnb nnc nni nnn nno nns no- nob noc noi non noo nor nos nrb nrc nri nrn nro nrr nrs nsb nsc nsi nsn nso nsr nss o-i ob- obb obc obi obn obo obr obs oc- ocb occ oci ocn oco ocr ocs oib oic oii oin oio oir ois on- onb onc oni onn ono onr ons oo- oob ooc ooi oon ooo oor oos or- orb orc ori orn oro orr ors os- osb osc osi osn oso osr oss rbb rbc rbi rbn rbo rbr rbs rcb rcc rci rcn rco rcr rcs rib ric rii rin rio rir ris rnb rnc rni rnn rno rnr rns rob roc roi ron roo ror ros rrb rrc rri rrn rrr rrs rsb rsc rsi rsn rso rsr rss sbb sbc sbi sbn sbo sbr sbs scb scc sci scn sco scr scs sib sic sii sin sio sir sis snb snc sni snn sno snr sns sob soc soi son soo sor sos sr- srb src sri srn sro srr srs ss- ssb ssc ssi ssn sso ssr sss