CINXE.COM

Just a moment...

<!DOCTYPE html><html lang="en-US"><head><title>Just a moment...</title><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"><meta http-equiv="X-UA-Compatible" content="IE=Edge"><meta name="robots" content="noindex,nofollow"><meta name="viewport" content="width=device-width,initial-scale=1"><style>*{box-sizing:border-box;margin:0;padding:0}html{line-height:1.15;-webkit-text-size-adjust:100%;color:#313131;font-family:system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Helvetica Neue,Arial,Noto Sans,sans-serif,Apple Color Emoji,Segoe UI Emoji,Segoe UI Symbol,Noto Color Emoji}body{display:flex;flex-direction:column;height:100vh;min-height:100vh}.main-content{margin:8rem auto;max-width:60rem;padding-left:1.5rem}@media (width <= 720px){.main-content{margin-top:4rem}}.h2{font-size:1.5rem;font-weight:500;line-height:2.25rem}@media (width <= 720px){.h2{font-size:1.25rem;line-height:1.5rem}}#challenge-error-text{background-image:url(data:image/svg+xml;base64,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);background-repeat:no-repeat;background-size:contain;padding-left:34px}@media (prefers-color-scheme:dark){body{background-color:#222;color:#d9d9d9}}</style><meta http-equiv="refresh" content="390"></head><body class="no-js"><div class="main-wrapper" role="main"><div class="main-content"><noscript><div class="h2"><span id="challenge-error-text">Enable JavaScript and cookies to continue</span></div></noscript></div></div><script>(function(){window._cf_chl_opt={cvId: '3',cZone: "zbmath.org",cType: 'managed',cRay: '92d6817f6b7f3f8e',cH: 'PTCv2e68jQWsW5x_AXODxxHzytjq5fQkg9FiOdVj.GA-1744165022-1.2.1.1-H88oZ6m6XE7mT54Obenhg0WhLOdjNy_iPrdAC4abeQK5SUPW9DV2u2rEbo9UoMLD',cUPMDTk: "\/1337.60122?__cf_chl_tk=LX4V2Iu8rzAQ6HmVcj05z93iO40QSV8i29BRrpdX.vU-1744165022-1.0.1.1-RjoV.Lde2r5tXIU.94gPGbqXN08AmqvdTTpqMAykk0s",cFPWv: 'g',cITimeS: '1744165022',cTTimeMs: '1000',cMTimeMs: '390000',cTplC: 0,cTplV: 5,cTplB: 'cf',cK: "unsupported_browser_beacon",fa: "\/1337.60122?__cf_chl_f_tk=LX4V2Iu8rzAQ6HmVcj05z93iO40QSV8i29BRrpdX.vU-1744165022-1.0.1.1-RjoV.Lde2r5tXIU.94gPGbqXN08AmqvdTTpqMAykk0s",md: "JCIhaD5XLa7sCDTDH4NUvapwYP04ZwvVgMQcMG78etA-1744165022-1.2.1.1-K8yxdrqb5IUsPVa.Wmw6aZL5Iw63bQ_qQ8MJx6IMODXUVNPFmLEkuJ7WHCaKybFxuMmPxw8UlN3kwv06md3ZNXaeb7xw2HaCtaXaJkJ1yErwsFnmuVT_lHTsIMRVzoYNpXAqEp34SvcIGxtk2ct1URcJM92QReAw5gpCHhIC03Jo7U6mJd9JuWhSX8CSq7aLxxzJW.U1aTW6pLrsdPZj38ZS.hYnBIsQWJXphZbD.jzV1KuN0G0NNKbj1ByMX4DUN2z5_kyF10l6qNV8TbynOsXoAZIwcGcRyffUkQ46BpQqXqPY4Slndt.hkvE5cY5Tx1CzpRWZ4ZeOsrezbwG45H92nMIgyYhhSz7Ess3nMLauPMZfyOjug5tFMRteIB7DB6Xndi911vKdozZSIyvd1rHvvmcZwQAmZBRMg2yNn9pHQE7XPsdeJAvBSXJPYuf9WRl3loyAZrVvM8ds2Mx3SsFJ4c4dc2YiY1UUgHJ90N.gQB7Mb1.4S1CCDp.hI4hQqJmuPKacbyZGCCFH0RTrMO0MvSVcoX1YVFOChElDOMXCrEx7g_wCb5_7h1fA4OnalCd0Qa_DQsHdCqX9CIsBHAnTSrgJLYSaq2iTqh4iMI7Kv55L3gtTZ81AGNrab4iR.98RbT67vzICqTWQZeWFXLJYHnKe5wZGe7AXaKU_BQ6DegHzfzcwkkKv7saYnWVWH4.V8gHj9OQjKHJfrrxYARz.VEI2w7HMDSPkx3CoHNQKkgI_OM3PFu6F6zV3Uw65fFmqLOsgDncDv6SyTHR6rBUIEBIU8eF0C8oga8Je4IBtryTaUYXvinOfQUJqxMmbv_UfDcT5Xjr95Wl2nsWFCXYIoeoXtPg5OCLUsJYOqioWuyU22k7jJ_.vQ0xOj5EXHYLlaDq3hrVWZV4S4MaaISBOxztNyIHAldi4ZYm3WN8BtaUM1rFDKeVWtmzCI5eLITFZ2AIhjxtKhrpZmm8sKRkUdDpRb3eLuVFjBaCcRA7YyxvlyanIDid4xm11gq_a7BlWBAWrTiUJLOij3MTQNc7snB2fa3wQyciLMQN2l_goutKoGrY9qAvX2G.ktpkwBt8lWKX0fDGPSe3SPcnC.n43YAmWduTs0DkxcqEDOkWb56gDzX2jrWcar9rPjSallt4Ggx0vrkui.eyTo6ZhvA3y3nWLjKR56YvH3re551xFBro6ZbvJ6iNZfR0bbDTB",mdrd: "SaqlSy61Jp7mu5xHTWv4kRvCiar6iU.icGJDloCjako-1744165022-1.2.1.1-xzq8ANk8zV8GHokwd.c7atEtE_KKxF3835yxsRAx_rt9fkRxyUGzMNM_jGMdJHmT2t8STossbKLXClhuF8rfPCdCwRdvUDBNoFOCx9fwvEyGTdvE7aVK021vbuzDV2iO7m17bKBFve2hcA._7QsxaJL30_ckndFkZBDB9dwzhNlxOZUs6UknNmcRhCiMaAwGMN5rfx3zUkZDKfvbg5nZ58wcrSaVkpyqpEsY4ARpztd5DxWLVeEnJnKg7aEvSTdTIy_jYYs6M8iXM7YjWz.tD2gMPKy8Zn4fuqMKz9ciyH7w9JBvMThmulvSzQRudkMiTKZntHsCITevoZ1xLScKN8u6TU60RF91GBc4Ght2OKsC7xTZjOxrCi.0z1aum3b6AY4bfjQwS3HyWLjdlSr0NLs93kIMw3Oq5ksbuoZFl71sPd81thLgodMU62X7ieig3whwoaKIG1C03byZF7.BrFtdEf64fozUp8G8DNc18zYghp.gkfgpkIfQ60Y85pee3rylTdrCyWYG4.qno14gAo77BCbM0FAuLVezwKJgm629P9acbv0zKQyXmnrBPWDNV0X3LrlVnJcwAXk9fxZY8e.1MQW6iNBSIkTtbO.Zmwr_Fk1YbFXYACjf3RUacBHLd2eucz26FiYQvGjMu_jVfhIRVyTXO5aR1YMltigXzKbRHLbtclznyt003ZTGOowV2eTV8Z9MfMKcb4CFzvrJuDYUki4movJoY1KmcmFgJ8BB6OEhAcYHjoPZpWpA1D_RXEi3GEBzomBXBPjHlSPufC5sMoYeNPM0oYTmgDs2IIraCAJnjSrVEippRWlnQpPB.Mz3D1OmTLua2Gbk1hE2NjUhoUTYaJrMbcTOAG18Y.j_kiapvHoaDUQbNJES8iS7nm3tWAgYbUZz9yL7prUuG3QrexlVJuKTSrgmIXVJR7jPPQIQk3Exagx5MRWeSwvK7QjL1tHHdO88U5U3HjzrAn1L790EfA9EQSmyXTYT__p9T4FU1uKLbuQj7GU7igsM7.9Dn_7H0PQnc0SUmLwHwb1LQk3vyWdKszzmCUDb6bgCDiXlBSMbjnK2XTcbLbZAZCf_HeJbCTNtqWePXtW.kL1gCobHRPUyoI9ql0blLTmY0xAk1bxdChR12I3QEZpVlPa.d28u9u1zhlSsHy8QZBLVWpL2IdlBnyilyNCEBHsdHKVXgWh_oKKhpNX60Ts0pUoy.Zd2aggVwF8FjBEz.GpvClkLf4kDpi6a34fq_TkqEbmVefKIHYTq_3zVFKxY5OLHVqrCEWY3R0bDY4WfyieABpk7RwB.TM2AOq.su9KbuXyk.m5m.aQN_TOTroR4pUNT23Vp9PtuhTjzU_N1Zo7a996ZUZNZqognTiSAHT.EY231Nbj5Cg527jjnwX0jmq5bMlvtUtCk9qyUWtHvfoGSGLk05Q2If_wIEdX8xHmSR2v5OhXtl5jRZtYHVhGtegtwGAfB3ddGsfoL.0hWcWrIPloylhvhJHZAo9uvPbb07S2Ler0BflcN0ZRUl8f8NbTyKba_221zvfbGMFiJ7tJSo9I9yKDsEGwdm4dekPmps2KhoJ.678IwPVr3Q092kBv2Dz9OICeHIs3KqFKR.jmuzjJkCUqiPv3qClfQYoYbhX.cXAq5bY3isZUNsqK5EbWG22R9rTvaQtEdqZ4hO1bjRiBzUzg9iXqHl84Sd_RMmd_6tNWCC4km9HhRb6PdFYEEHksbZx3100lrU4v23z4bTRdJRMbqGFMAfmku_2ULZhEjFFM2NMn2I64QaMbA6yVio8IaZcfJghstPt7NM2.4S3Yiby0d7i6thGJjyxd8rxZZQ6865UDYdPbTFfNNzGToan.QE2poXHzyOxbpXymOo3umn5.ZVZYacJowdao_yx8DkZ4PY0FUHV60Z77vyqQVtgBjoH32.ERmjNMdvFVegpQx1Wrq90FSI8bGGIZjiJKzXeZWWTPPa1_homPWaJ_d5QHndCoEZFN5hSpQQZB5D6ktxRBR8P6mVOtfBHZWi2WAZM2Tlh8iThcwBaxK"};var cpo = document.createElement('script');cpo.src = '/cdn-cgi/challenge-platform/h/g/orchestrate/chl_page/v1?ray=92d6817f6b7f3f8e';window._cf_chl_opt.cOgUHash = location.hash === '' && location.href.indexOf('#') !== -1 ? '#' : location.hash;window._cf_chl_opt.cOgUQuery = location.search === '' && location.href.slice(0, location.href.length - window._cf_chl_opt.cOgUHash.length).indexOf('?') !== -1 ? '?' : location.search;if (window.history && window.history.replaceState) {var ogU = location.pathname + window._cf_chl_opt.cOgUQuery + window._cf_chl_opt.cOgUHash;history.replaceState(null, null, "\/1337.60122?__cf_chl_rt_tk=LX4V2Iu8rzAQ6HmVcj05z93iO40QSV8i29BRrpdX.vU-1744165022-1.0.1.1-RjoV.Lde2r5tXIU.94gPGbqXN08AmqvdTTpqMAykk0s" + window._cf_chl_opt.cOgUHash);cpo.onload = function() {history.replaceState(null, null, ogU);}}document.getElementsByTagName('head')[0].appendChild(cpo);}());</script></body></html>