-er b-u bbb bbc bbe bbn bbo bbr bbs bbt bbu bcb bcc bce bcn bco bcr bcs bct bcu be- beb bec bee ben beo ber bes bet beu bnb bnc bne bnn bno bnr bns bnt bnu bob boc boe bon boo bor bos bot bou brb bre brn bro brr brs brt bru bsb bsc bse bsn bso bsr bss bst bsu btb btc bte btn bto btr bts btt btu bub buc bue bun buo bur bus but buu c-- cbb cbc cbe cbn cbo cbr cbs cbt cbu ccb ccc cce ccn cco ccr ccs cct ccu ce- ceb cec cee cen ceo cer ces cet ceu cn- cnb cnc cne cnn cno cnr cns cnt cnu co- cob coc coe con coo cor cos cot cou crb crc cre crn cro crr crs crt cru csb csc cse csn cso csr css cst csu ctb ctc cte ctn cto ctr cts ctt ctu cub cuc cue cun cuo cur cus cut cuu ebb ebc ebe ebn ebo ebr ebs ebt ebu ec- ecb ecc ece ecn eco ecr ecs ect ecu eeb eec eee een eeo eer ees eet en- enb enc ene enn eno enr ens ent enu eo- eob eoc eoe eon eoo eor eos eot eou erb erc ere ern ero err ers ert eru es- esb esc ese esn eso esr ess est esu etb etc ete etn eto etr ets ett etu eu- eub euc eue eun eur eus eut nbb nbc nbe nbn nbo nbr nbs nbt nbu ncb ncc nce ncn nco ncr ncs nct ncu ne- neb nec nee nen neo ner nes net neu nnb nnc nne nnn nno nns nnt nnu no- nob noc noe non noo nor nos not nou nrb nrc nre nrn nro nrr nrs nrt nru nsb nsc nse nsn nso nsr nss nst nsu ntb ntc nte ntn nto ntr nts ntt ntu nub nuc nue nun nuo nur nus nut nuu ob- obb obc obe obn obo obr obs obt obu oc- ocb occ ocn oco ocr ocs oct ocu oeb oec oee oen oeo oer oes oet on- onb onc one onn ono onr ons ont onu oo- oob ooc oon ooo oor oos oot or- orb orc ore orn oro orr ors ort oru os- osb osc ose osn oso osr oss ost osu ot- otb otc ote otn oto otr ots ott otu ou- ouc oue oun ouo our ous out rbb rbc rbe rbn rbo rbr rbs rbt rbu rcb rcc rce rcn rco rcr rcs rct rcu re- reb rec ree ren reo rer res ret reu rnb rnc rnn rno rnr rns rnt rnu rob roc roe ron roo ror ros rot rou rrb rrc rrn rrr rrs rrt rru rsb rsc rse rsn rso rsr rss rst rsu rtb rtc rte rtn rto rtr rts rtt rtu rub ruc rue run ruo rur rus rut ruu sbb sbc sbe sbn sbo sbr sbs sbt sbu scb scc sce scn sco scr scs sct scu se- seb sec see sen seo ser ses set seu snb snc sne snn sno snr sns snt snu sob soc soe son soo sor sos sot sou sr- srb src sre srn sro srr srs srt ss- ssb ssc sse ssn sso ssr sss sst ssu stb stc ste stn sto str sts stt stu sub suc sue sun suo sur sus sut suu tbb tbc tbe tbn tbo tbr tbs tbt tbu tcb tcc tce tcn tco tcr tcs tct tcu te- teb tec tee ten teo ter tes tet teu tnb tnc tne tnn tno tnr tns tnt to- tob toc toe ton too tor tos tot tou trb trc tre trn tro trr trs trt tru tsb tsc tse tsn tso tsr tss tst tsu ttb ttc tte ttn tto ttr tts ttt ttu tub tuc tue tun tuo tur tus tut tuu ubb ubc ube ubn ubo ubr ubs ubt ubu ucb ucc uce ucn uco ucr ucs uct ucu ueb uec uee uen uer ues uet un- unb unc une unn uno unr uns unt unu uob uoc uoe uon uoo uor uos uot ur- urb urc ure urn uro urr urs urt uru usb usc use usn uso usr uss ust usu utb utc ute utn uto utr uts utt utu uuc uue uun uur uus uut uuu