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: '92d30452187cfeae',cH: '4yz_CdaSrAj.VzEpWANYyxTxvytASSJMGbICD2TCwLg-1744128438-1.2.1.1-O5FWF_Z2589mzEqX18GlPuSFuIfgvMe0ZkHZLwYndsYRTsQvi7RfxzkhUqxiNU48',cUPMDTk: "\/1277.28009?__cf_chl_tk=uNCQSXu47w9wG15UsKerHjt7NdxMHkpVtcXCx7h9RDs-1744128438-1.0.1.1-LZNa5CwET1lCJctxh3w0SSi8qh3u0qBkE7ZWJlo8fZs",cFPWv: 'g',cITimeS: '1744128438',cTTimeMs: '1000',cMTimeMs: '390000',cTplC: 0,cTplV: 5,cTplB: 'cf',cK: "unsupported_browser_beacon",fa: "\/1277.28009?__cf_chl_f_tk=uNCQSXu47w9wG15UsKerHjt7NdxMHkpVtcXCx7h9RDs-1744128438-1.0.1.1-LZNa5CwET1lCJctxh3w0SSi8qh3u0qBkE7ZWJlo8fZs",md: "ATNSTI_bYn4prncDOq90B5Qrw2MOZkyu3Fl1b17spH8-1744128438-1.2.1.1-oZU1V3Cp9n8m9ns1WYIJGcG1mRO7bc.NZ5nrWDilg0OSv_N3Q9qt1rUhrnIj3tzkCawqiPAPG0N769lh3verey7W_AHSZxpmHthHWaXleFsImcO0OBdDH4axcd4hCqmwN1nyIRF.G96LAfYeR6RG9xjlIMVw5Hfg9y7Fq2MrH_KFm3kkfxLNjMW0ba_ifGRF_senY9DhAJcCEkjw0Wvd4jrH6lJ5xy17qGa7WyLlYVgWW7Xuc.K19ByEsc37Qu7kRAc3pd3RxEl30w.s52UwcJnSNIzGKaiwVEBfEHrIV1xAUqESL4Acmqdfo9OduIva.WQdqKB3NXt_rhCUeIGHCTwuRgvskvfSpWn6eaKZUh1OMyT8mbRpShLOpUaIEMhuvC0PTMyLJb7jeyZcPm9SXFBcTWwINTlaycEXlu1I5YPT2BNUcsyW4b_4UeB9_nksO.g9B5Wq9fh7QqE8KX0SrmM7cndychFQFlQHgb9ovGfjt0DfE5OH2WIMm7ExHAYfWVhHUBTDoayMhXcEK1gZp6KQv_PGUV3Gd.EX.ioURZJr5TlH5HcfbnXp5_mulCzD_KrQIZH3LeI3ibJfwXZdloEEus5_yT_fw6XWKng3u2ZEWY6dA_Nh9X8Q9zCcIbOOi33iOOLaRudjxsrWku5F7Es8abeJUSfA2Dh3IgKmZWXk_vuVRV8qCPVzXwwTmCLyLf9GOPZZQxSqohv9uqYgpUHH4lrQ5iBDodabtru6C2r_ni_JM4fYLDakrz89owf5lVL4WJ93Gc1EbrMbiu4BAzeV4kUvn_bMaLA1Do.vBLfqZg4lMIzziKXlsBbnE3W90iRVUQjWkh5ciy0H5XGOpCLGkqqEUnG5q9mgBaYZ4ipgOxtDvWtCwDhgmHG1VWbN69e_RyuuEiOHUAltL_gLCcAaB1wB6qxifqMIaG1SN.aRZqJInzMgBFDj2U69ikSdXfeTaR2sX6kXyGKMUhF05XWjwp6BMyoF0prWDJTxw9cfjBEx__01FieZnz7cFX9gCfCqyHirkaViV2jsKqMdr107hgDAL0N7erb_Vh8dIRWHEpkVLBBZdQAkQRwNdMUrm__oAkZzRpEacNoFLPuH7vXuiIYdKGAKAXQfNeKCud_fiEokMPcP19HaBcLkcPVN4ahBFmaGa85LqrF7tYwQOijJEMfq7Yf7hpe1wlQpW92dOkQo0D1IUFgk.E9g1amg",mdrd: "sbXetMSo7VceP0RqpBSkyorRJhPs5Cd3IFolJ8Qwk1Y-1744128438-1.2.1.1-L2ShJcpKK12ncdyxLYEM5p.PXPUkVBJE9F38C9u4GL8TzaR.7eOCjaBzMBLFYx9ATq702zI6JhtFmPTkCarGOsgRzNEwGWFAdsskWYMGBFc73uz997YELufc.ZIkulolgHRsQ7fAXIQ_Y1WSdlbWmUwhZYTHVyLSsR_UTV4.7WYjDb0HRVEk8Ma03UdWdGdJUUu73ypM6JNrQbAu8KRsP8VdZM9gvxoRuZAAi59fuSp0VqAKc.Z_qlQ4KWUcBGOX4AlDAlwS4iwomibsG.t20yCWtmaCjWPjUTHpC4O_gaMwVSe8qDTbuxryHA0Z9zxn3KvvAfgUtoDeCLycpjL_RsTaAc3xPbEuiXC8MFytabaGr4AHCefOgwEVwyHcA_MWRENd_bjGhMvouBV2TjRi3ksdW5P3lJWE4Mput5UHbRy4PUfH783GyNWdf9GJdlCMROQtc9ckMPl3GQwytA13LMrf.vcKiQMS.xlAOKgFDL2wGjX9v3HNaocJ7swGN1F_CcwMLOw0vz2F61En48IXQlqeMfeo2WoIFMEOqrPB62JGWE8ZhsXul5OBLuf8k8wB5UE9VxvZ8Fdfb9pPaPr.VHb2Z3QYEHxZsQmk_P._6wt9etKvcJr1D8YzNy2QYKPMxarF7Y.PQzw1ytSkkERgUGWR1wc7me952UzhRdz60RrOtO0CdtA51tVi6RVw7U73BMlINgXQLLrhJvsNkWk_593Wj.yR3_BN2OXpolF80aPU95OepUAD8n4sIJLR87iDzLoy.hvKHidFrmeDIsxqhVNJc6HmAVRWH.lBCUL17tv391Ip4iM5n8Ij.kSwI3VPFwr4QqQ81HxXmiKCgSp_iP30F2FgmEoY5JVhypZVOWiLS2V5S_rwROKe.TaxYq_mGCc1ttA8glG960bXi.fPKMEkcL3MTa1jY_.f0KwPOfUOaA_osz_JTrQqHysg_IoJjLaB1UnwDpo5ut3j4HaNsAlpazvruC0ADAszabBa6PZaOJSvxHRSpsrPuDAFnXVudL1my_mlcja9aRkt0IgmeAF.wNEZkuII5PyyrsTR8CBZ6mtwJADJUP7roax.GwSKAmNHxWuIp1RAo081wh__.q4owl0ddIUlaVLmo0_QttR4tPYtNzfMhiTs3iH9MiiNLLWM50O64VZol0TwMbhzQCNiw5fHmJ20zjGc1Doq5UfnlUNjj89BjvZ5vx7FVxHUaW6escewJwfwaWRABKG.pmR0iwQC65EfgMW.828q6EltYAcohdMUhcLr11EMycwbAqw9y0HqGNo33L_JdvUwKs6v.Kx6UHf4nhYH_TEkHHvg9flbVnkZi4_YQMfI0n5425AeCLtWAKzDeadCRkQCXTm1GRclSsfi6H3CD_BBR3WL5VfMNyZgz09dUrmpqrvgIzxqasKWU.ngOCoLfv1Hg8VE5DbKCWhrZ2VEQWY0aLro6lVJlTM2hYPtNNhNXDwkllh8ojHb4H0ImN.6KGJAmMQgjE2ggd0bPncDDMw_YHcWC3sxK.uh64wP1.7pjXvYQL37OwtV4ZOtoZuINAaxeUbWm00oBbqepIUkehMseNLRMn3.NJJ4sJZaNt2i48iJMV4SPeB5r18QjszG1HiJhblonTKPciHNMqNgXRglv.jaKO26W2XbJF3ZWffk2Bgu8H3YwvcpL0sRptdjqcPPC0lZkkG35Sl2HkISK13IZWmArTr3GpE5wbC_rwYEoH4Sdy34zlQX5Yn6vni7qnndg6jTTzIN7evshnx1q23joUZjLSRWJZMbj9CbyY_LLWhckaYOP7sTGJrECNK9yXMeDrGroh6750745zRcghy0aSId75In__.cTCscqKK2eRpshGrvUkdolov7N8qzxUooV704YDw_Mtp0A7.sm6RIb8k3E3Di8AH5N7tW8ViLq4YSIwjKMz5FPLUmeIaYgZUZ845gKA_45hEzup2f_deJ6uzYI7hhI7zcs0NDPIiaud2BAhpNQVeFqVxkx4nKPRdZYj.AHT0ZCMc9NiQ3W4EP0aE"};var cpo = document.createElement('script');cpo.src = '/cdn-cgi/challenge-platform/h/g/orchestrate/chl_page/v1?ray=92d30452187cfeae';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, "\/1277.28009?__cf_chl_rt_tk=uNCQSXu47w9wG15UsKerHjt7NdxMHkpVtcXCx7h9RDs-1744128438-1.0.1.1-LZNa5CwET1lCJctxh3w0SSi8qh3u0qBkE7ZWJlo8fZs" + window._cf_chl_opt.cOgUHash);cpo.onload = function() {history.replaceState(null, null, ogU);}}document.getElementsByTagName('head')[0].appendChild(cpo);}());</script></body></html>