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: '92e2fbc8d814f8ef',cH: 'gvhpetfyHyvB9u8MrLKLcOkjq2W9eXiLOE.0bX_mDRo-1744295860-1.2.1.1-F65Z.doaUIexzXYTC_X3XdTz_roQ.11K5mt5Or71j6k_H88YqFWy3fNiiXDKrZHW',cUPMDTk: "\/serials\/2831?__cf_chl_tk=jCkwCLW0A8RuqOJcaoMMdocQ3qUisbEceeBb0FR6olk-1744295860-1.0.1.1-T79hOiFo7c7edgi9SXew49tzH6E5_EbaF06fTgMwkyQ",cFPWv: 'b',cITimeS: '1744295860',cTTimeMs: '1000',cMTimeMs: '390000',cTplC: 0,cTplV: 5,cTplB: 'cf',cK: "unsupported_browser_beacon",fa: "\/serials\/2831?__cf_chl_f_tk=jCkwCLW0A8RuqOJcaoMMdocQ3qUisbEceeBb0FR6olk-1744295860-1.0.1.1-T79hOiFo7c7edgi9SXew49tzH6E5_EbaF06fTgMwkyQ",md: "avPTZWYmlhUZtLcvu5XYit6x3gi7fTRA.OM1DzhHwTc-1744295860-1.2.1.1-pRJ7V7pEdxc4LlTWv8tx3xJWxJDUV0w7GDKopDTRah0g8QLRh.jWKnHDJU9wM2U8tT9qwJF7ISlNXhu2w9LQA.mVckpGK_jgxWNOrYPiuCB1hlC8K6u89ZnWURc1NiWBGfaquwrgwtbyngM1orxHiWTD3oDE513T2TK7ecL0WoUmL4mfzIV2ILJSuQ6hVh.SeUPgT57MSnSubBOHxQ52Yf7doRyTpZQseIPPCjqQn_G8zuw.nYYQ1huWhK92FisDhOPaUCGOV3GlMxiL3tXgOigM.qEmqaFB7NLWeNPKzuAvkKKHmlbLns0brXnl86Aa3BnvEmd.dC1HOHC4H_lTdqxmb0UI019CXUFMnCPFI6F_lKNNRUhc62kSzceFeB1r94JTPuXoOcdk6EMPewTK7eayck2BRq4sQj8uK1owYKg8rbSoaDqMjcDBI9pfHh7k2CBS7LTPtUrtxi27ZNI_cYOb1ACkyUOFF5PRemDH4V8_PVanCQQHesL.I4fIKjmmcvRe4ZaIucuBSdGhvkE3g3zAqGFbYOxhSps_IT6pzv.G42AAATK_IkA.8FgEPyfWDjlF.Mp9FB7NcUc_TR3odk3UUFMoztWVEq1wBkD1mI_T0.PuYjRKpn882g4igDkSDO2SkYoaITOpZN2KpWMcKRpa9JmCGnI8OTtC6FQ2nvSXagKSFSWoR6EOvAabmzsRf1UEwkrUfPUfqCXWOKlFW8AdVOM5ZAFgNJy3z2URtMlw4AeQg_6HmNFCDFFM6pLonYqtOWCtpww_Bf9j0FVSEmHdVcRF1QmS.7ZM8OMY0k0HR34fNZJbgnPR5o.J1_CfHAItHiJ5nk_E_NeLtGL3TjVQ8A6rb0hWAlaRePbLV2FxRxF6OqBXxyPXkGYB4bqbjqycVfhk32d23kalRZr0Qbjjwfq0AwveQIGgGbxNh5niC5gYRJHuISW7JPUqLqJCDyvNeaOws79ejra3L2OQJyW5lF6tgMo3bRGIOMAznX3olUxRDi.pwSS299zMLZ7Kw0Tg.sACSfbo6MM4iB6zmNupTEDatmuRp4G0dsQEoKM1ojq8nZmlrWaQ3e.E39lgZG.PfFUSfwT9QmwDstW4KzFKPWsgqfkSXTf2pK8Sg25UsTnV6QKf4bACM_bJEEDr2YYiALvDOgv_xGO_7UHfuV5T7XJwyzNyJvycciCtaqnq4l0iAJuUMdMWYtafml5l",mdrd: "j7W1.IVvM36N7eEcrTLIuJ.03lrGesEeoyzFz6v1O4k-1744295860-1.2.1.1-63cgHVZ2AP1I4C4wrhdpImr3Y2lsa6GZmtOF.WWrLBGK_BIiD.edtjxM3nuABScPMZqFhn59OjdotfAgumMTgYFyryla_gHy.yPNfSf9WCUSzgO6bKQ79slbpjdtAnYTkIiQJEtfRiTkAxTMEysVqYgPBRdtB_DyjV9IJrAab87BglvuFq9H4Qp0PWp6Y5JHFhGUGgniObmYPl7AllDn5TVZ1CwzwX8ity.khAss7TIcgQuRQBFtZRFNOethwW7chkFolDfJKWURrPzzvrjBEpf31134OpnyH2PJLdriLvCroMyOLoYphImgJeKnEVaZxn.ukGjHvFzhQhGJ_1RwR9rQrGi4lydQ5D23OTuhqacz7iTTplrejn87x5uzM3cPgntk.4cdfD2JENvWZdfn1lu_Gob..BTtgTRb8Iq20KBCB4iyg_Qz85EleMpH_9ExLcoYxlrBztglJ23xzvDPU4i2Rqoho4YEX3HCjEDAfXuiFTT5OdXnwliP0NR_jNP1R7FbYKe37hDE6IKQysrzhu0P5JS76tDudacvZ0_5abdqmbaBl.spE75._i00Gu4OyGIBXlAfrwnmSkH8Wki.9nSoIgnfdmCV99Xej6B_dhZwNFVi6PzVhZ.waAbcHQya6HMc5qiGOcDTMTQshFV0WTMYwwYSLLMfOl75gMH3sPxUaA5Xnzh21aKl1FnmLlNpQijk.ROB.mnq8aQiNeHtlmNYsTStYsMCx5bE6_hURDwGN2ofF6rCyillT7lWKyIBbH3Kn7TndPx63.0zMi54Ycaxzx_5tEKTdouP7yPjHkdAcJmpybUC7UuzJzB9pjJ_oZlNKs89sis7Y5eq__MRmofsplDvK2PY4p2_S.vSmwyPyNvipJNPS0KaSlqZvvgBJrJw_XG2O4qoiKDPq.1Ri8783zdCApMi28ypPRgZjSWXk1xFTHlT6I8BWAjFj6La9YAe_POqzjFGqu9uelEyy3PjuaIAQqzt5i7dj4Sg32.JOp2LkAOljLwH4Ejn0An_Yaj2QhnW7kYbWSisVFJZRbAGqWTcJh_P.WiGhOCb5rAiWWbzaPkapdCe8Wi84UTnLCDyvnSAMfORr0Mmd42j3m5GEFDWZqkmdNiTE5g804F5a7qd_K3RPKerMZKsrxAmaeGPqMlsbWcdZIiWDIK80s6I2b3XPDdCQB3.wIzRPfRiW.yhnMYOY5jN6SIHDTSqmNmVWx66Xrx.PLIvPNXjO7Hsluq6qOEzgyCBx1qY81mNYYM7dQYNceiOqDg1qiI55rh2xN5Y0nOpVNH5kLVZNRGMr64fan_50u9IybRWuZ306bW9XZ9kQ__sc2fQj9_sGNRY8oMJHXfKheTgiynCJ42Ja0kFbl11ZPDeKtpWjzmd44s0Ec4QjFnFkkBJx0uvGf8bGSwvk_Eq80kMya8LXadsCkz0wskVHHtskwp.eHEJS7ksJQ0wRPKY7LGp5ZAm5MaJ2VlioXE9ezRbkgHZ2z7JgtfF.cS4xONmRseJmYm.5AujOkRijYlVN7ZFGbYhmvSsuPzatt34Mf.rXLD_BCdukJLYhopJzQukk.xSXSp3toSB5BXSIIYAKp6UL84wCCdsIUloKLuQZuzrWH0uvUWNp9qfrNhcMN5OWLP0nVUymNBfsRzwQlgmdgGquXMA7xeLluq1cjrzSs2bdptzcAo..jmu1RiyKAOnvv6Zis14DWNaNFozExzXxvM5XYooS036bE2d2WM9uRwBA8V1CjesaH1PQi.zMJ2k6oijkJ7bFwpRj7y9nfvpRIEckzI6vC6NRAdpoiIqJLvQIWMskvTC.x2geVFOMZ7h20e4WnDdC1lQD0450T0q3ca7cIDQ4ZVBLEmcQi5cD0nuaUlVO6bV1RxvaxYNQVmcYgNXMWcIfDgJlKu06gElDtYpOPiE9ptXuM3gM5lrg2WThxc2K1VVfkAeb076LQw_mMr_vs33Z7caPCKp_Oss8PqJC0oPPR7wZ2ewM44AVNoWMQsnThRgOfcaYLD6Cj1TVkRY2uP.DmzpY12jF6_ZRkoBOcvSa_l76tx5m5uCuNCIItGAnQ"};var cpo = document.createElement('script');cpo.src = '/cdn-cgi/challenge-platform/h/b/orchestrate/chl_page/v1?ray=92e2fbc8d814f8ef';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, "\/serials\/2831?__cf_chl_rt_tk=jCkwCLW0A8RuqOJcaoMMdocQ3qUisbEceeBb0FR6olk-1744295860-1.0.1.1-T79hOiFo7c7edgi9SXew49tzH6E5_EbaF06fTgMwkyQ" + window._cf_chl_opt.cOgUHash);cpo.onload = function() {history.replaceState(null, null, ogU);}}document.getElementsByTagName('head')[0].appendChild(cpo);}());</script></body></html>