b-u bbb bbm bbn bbs bbt bbu bmb bmm bmn bms bmt bmu bnb bnn bns bnt bnu bsb bsm bsn bss bst bsu btb btm btn bts btt btu bub bum bun bus but buu mbb mbm mbs mbt mbu mmb mmm mmn mms mmt mmu mnb mnm mnn mns mnt mnu msb msm msn mss mst msu mtb mtm mtn mts mtt mtu mub mum mun mus mut muu nbb nbm nbn nbs nbt nbu nmb nmm nmn nms nmt nmu nnb nnm nnn nns nnt nnu nsb nsm nsn nss nst nsu ntb ntm ntn nts ntt ntu nub num nun nus nut nuu sbb sbm sbn sbs sbt sbu smb smm smn sms smt smu snb snm snn sns snt snu ss- ssb ssm ssn sss sst ssu stb stm stn sts stt stu sub sum sun sus sut suu tbb tbm tbn tbs tbt tbu tmb tmm tmn tms tmt tmu tnb tnm tnn tns tnt tsb tsm tsn tss tst tsu ttb ttm ttn tts ttt ttu tub tum tun tus tut tuu ubb ubn ubs ubt ubu um- umb umm umn ums umt umu un- unb unm unn uns unt unu usb usm usn uss ust usu utb utm utn uts utt utu uum uun uus uut uuu