bbb bbm bbo bbs bbt bbx bmb bmm bmo bms bmt bmx bob bom boo bos bot box bsb bsm bso bss bst bsx btb btm bto bts btt btx bxb bxm bxo bxx m-o mbb mbm mbo mbs mbt mbx mmb mmm mmo mms mmt mmx mob mom moo mos mot mox msb msm mso mss mst msx mtb mtm mto mts mtt mtx mxs ob- obb obm obo obs obt obx om- omb omm omo oms omt omx oo- oob oom ooo oos oot oox os- osb osm oso oss ost osx ot- otb otm oto ots ott ox- oxb oxo oxt oxx sbb sbm sbo sbs sbt sbx smb smm smo sms smt smx sob som soo sos sot sox ss- ssb ssm sso sss sst ssx stb stm sto sts stt stx sxm sxs sxt t-x tbb tbm tbo tbs tbt tmb tmm tmo tms tmt tmx to- tob tom too tos tot tox tsb tsm tso tss tst tsx ttb ttm tto tts ttt ttx txs txt xbx xmm xmo xms xmt xmx xom xoo xos xot xox xsb xsm xss xst xtm xts xtx xxo xxx