b-u bbb bbo bbr bbs bbu bob boo bor bos bou brb bro brr brs bru bsb bso bsr bss bsu bub buo bur bus buu ob- obb obo obr obs obu oo- oob ooo oor oos or- orb oro orr ors oru os- osb oso osr oss osu ou- ouo our ous rbb rbo rbr rbs rbu rob roo ror ros rou rrb rrr rrs rru rsb rso rsr rss rsu rub ruo rur rus ruu sbb sbo sbr sbs sbu sob soo sor sos sou sr- srb sro srr srs ss- ssb sso ssr sss ssu sub suo sur sus suu ubb ubo ubr ubs ubu uob uoo uor uos ur- urb uro urr urs uru usb uso usr uss usu uur uus uuu

-ous bbbb bbbs bobb bobo bobs bobu boob boor boos bor- boro borr bors boru boso boss bosu bour bous brob broo bror bros brou brrr brrs brsb brsr brus bsos bubb bubo bubs bubu bur- burb buro burr burs buru buss busu buus obbo obor obos obro obsr obss obus oooo ooos oous orbb orbo orbs orbu oro- oror oros orro orrs orso orsu orub orus osoo osor osos osro ossb osso ossu oubs our- ouro ours ouu- rbbb rbbr rbbs rbss rob- robb robo robs robu roob roor roos roro roru roso ross roub rous rrrr rsos rubb rubs rubu ruro rurs ruru ruso russ rusu s-os sbbs sbor sbus sobo sobr sobs sobu soor soos sorb soro sorr sors soru soso soss sour sous sros srub ssbr ssrs sssb ssss sub- subb subo subs suor suos sur- suro surr surs suru sus- suso suss susu suus ubbo ubos uor- urbs uro- uroo urso urss ursu urur urus usbr usbs usos ussb ussr usss ussu usus uuuu

bbuss bo-bo bobos bobr boobs boors booru borbo boro- boroo boros borou borro borsu borus bosor bosso bours brobo brobs broos bross brous brrrr bruss bsous burbs buroo buros burro burrs burru burus busso bussu busur busuu o-r-b oboro ooooo orbus orobo oroso orosu oruro ososo ossos ossur osusu ouoro ro-ro robbo robbs robo- robor robur rorbu rosso rosss rosu rubor rubus rusor russo s-bus s-o-r so-so sobor sooru sorbo sorbs soror soros sorso sorsu sorus soss- sosus sours sous- sssrb sssss subbu subos subss surbo surur surus susso susus ubobo urbos uroob uros urour urous ursus urubu usour uuuuu

bbbbbb bobbos booboo borbor bororo bososo bossou boubou bourou bousso boussu brosso brubru brusor bububu burbur burros obsorb oooooo orobus orrour ossous ououso ousrou robous rubro- russo- russus sobos soosoo sorbus sorors sorous sorrus sorsor sourou sousou suburb suroso susurr ubussu urobos

bbbbbbb bobross boo-boo booboos boubous bourrou brosour burruss bus-obo oroboro robosub rubbour sou-sou soursob sssssss suburbs suursoo ububboo usurous

bbbbbbbb bo-bo-bo bobobobs bourrous broubrou buruburu oroborus sussurus susurrus ubbubboo uroboros

borborbor ouroboros ouroborus sous-sous susurrous

bobbobbobs soussoubro

ouroroboros

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