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: '92de17264c48fe8e',cH: '4anDqaXzbsN.HqKc1OGvsRBQg.aLT364AU3Wul1Z1vc-1744244552-1.2.1.1-S7w9cEe7ASWZAaxF4iLZv33ASB.jEU3w1AlSoeYZChr3px_EyEmKEPKbWInjMrEk',cUPMDTk: "\/classification\/?__cf_chl_tk=v1tmd5Yrpuec4cyEFOVlcf20w1NymokzLybrOzc5_Lg-1744244552-1.0.1.1-NqPe_MzET0fdILV0Nyefp_cmSsS3XhEs6GeZ8LBElk8",cFPWv: 'b',cITimeS: '1744244552',cTTimeMs: '1000',cMTimeMs: '390000',cTplC: 0,cTplV: 5,cTplB: 'cf',cK: "unsupported_browser_beacon",fa: "\/classification\/?__cf_chl_f_tk=v1tmd5Yrpuec4cyEFOVlcf20w1NymokzLybrOzc5_Lg-1744244552-1.0.1.1-NqPe_MzET0fdILV0Nyefp_cmSsS3XhEs6GeZ8LBElk8",md: "AZRCtjxtn6Xtao5MANHAVMBM4A8F.5VwmWUiVyUhQIY-1744244552-1.2.1.1-GJLCBO.xIs3b92hQfAdwN3zZXPkTnqYpA8oyGBqp.LlMr4PBsf.aXsH.B1ICi4.zsj2bOHOtmeB20c7G9t_IAAIi8rcq8bjvuKQlcKsOvem3.gUyMIirEx9bnsa0303HW2F7H.G.Mv6fErcBWaETsVrpA1ePYgA.lGNe_Dwbm8FwOLJnLSr7OGJi8zdqsZUop3mFjfJYqQYMcx5KZsWo4r0YyYvIwLEsN6CbvH2Yc5fteAU3B1RbZ1vpPDLGLqivJ5_ca93RLf6jeJg.dYIJhka_a52zpz0supq1TEzzxUJv9Frp99nlYJTNj3OWvpSOsDVCmKdTl4C4ku0Jo0061ZuksmKpR8CLWMdw.M5b4ICtHeCPWtjU9a6ALzEqk1G.bqWGCPPquXHPYKbIBKijiWVl8nuKb4TmmdO9d7IT18d6C6Ax.Yeegsro9TO89eUDHbBcrDMmJaG720rkFGdGL37AnGysQxp4OmKnGwRVULvJmviwKbBrgH1kJMjg9BLIqK.4cwjfxWbmPBpIOWqJu.kn.YWqL2gtrp6B6OU0KzmAEvEN4JMYvkQqmLeCWK7j2FtnOV3mvuKHSkAZ8B5EG0WIBklzvMn9UWslQnXMaTH4dnqvT6aBVu5.spo1pj1TRCegVPzwq6TJX2.wQXHPfEaj9jTlmmKp5uLsw1IRferjlpT._mOH_ZhBhROsedxyNnjBJVE8KCkISYUNS8lZ2hn8w1IUuR2lfCOs5rkMwUo9ToXhEOSblNq4j0yMrdcd0PI6e6.6fiwOcI9KoYPPnBaUKCtcHAyLvYtxnEwB5hSZTb6CgvVIik3.TyfniTBm8WP1MKMOAc.Hf1g3xHVibWqipmLsmURVWLVji82f2AYJOb2RvplLLuC3N.7GLPMuX2yzHGP3CE6.wqbk8k80iP8WcT9hriQ1M3pHOBmdagF9IZ.Y4AK3hBiZIlUP9clsdfHm0nzWRGyy2UdQLZ9YweQWuYRlMOxCQZbtOb8sCIMjT4KwbE0oNzuBrLVvo_I1gs65kgUfMoQYNsyk9wBLBCPCSEM9bgpyBayq723eHY8IikDxeM_6fC7qtgREaxK80285PjBuk01Uj_aCryfmZY7nsxy48Yiy1eAf5m0sozpi0yAjfUkweRouMDQ0qJJav02bCE82ux8eSvmVwKeN3SIG3OT9UprFBWGO7bdmXnsn2OG_PlZVbwvTSw1RBYOX",mdrd: "M5fOW2xNIMAFu9xG7WSSzD_ArGJSRKmxT3ZKrwjydck-1744244552-1.2.1.1-S4.Hra8qwJNl72aVR6DEwl48dblBHG52VP5sjEJiN6VyzSTxJrtG.h3I8romuYpBeCXhS3FgNchgud9obZUwcApTYdkmz4O8eq939y0B8nyt8tw6SWJgCfxbTqC4AlLUCzX08dbeUhJjaLrGVMlaClGaJqzdZW_4PUfrsWhEUvrysOau8.FBZtKSbpiULRcqE4yZZhprmw6PRiZepcC6dtFokFCRgF.0zu_zW.HJUTqaaWVZd1CtdTQd53VVEOJGGcD3AYmMNtY1s1._2Es6fvy90qEsqN4OUkUA5buIu74myTYSvHdtMYPtKsP751EWbZFezgAtftWGKAT4qOttJ.wMcE0vFLPA6hNMSp.fn1bfkFjzNAmD3Kbut66CXEF4UiM0j4JYRHNRW1DQmuZF8DbiS2mYwWz2_kV5MweFoCWs63prfMeiosjpyZe8r1zJhkOJ93Bji1ed6MpqKqtdRm0qrCpOUHqlgWd21SHqZDkEH0WGNfO99eHQX.uUFL1PgH6mEAiiB3veq2Lwwr71oedCQJbMvv7wdvCgNfgVu.iyI6VUb1gEyIuVSCOtWLBAVkoNuYGnQKBaOw_rCC2LLUIi328_MfSXvt_xB42Ro3XMDA27UmcTX7Pmq9bw0yTMc6EpjxQBQWd3DpRH3IuhTxSoiM.2n8OxXfrhOKURDCKaiisEd9mRGK7RsTdZ9dzQ6ATynDNnF8JqeD078.547hHfI3IpnZ4pvVtFtY05nXgR7eHLeBtSOwrVj77GnLLbDw255R3dIo5BaWeR37LTQon8ASnZWvlU2.CBINuY6XnUrl1pBgJ7_eh6HgJFxlmYYGp165EYy2v0vnKqD.iUX6ZpGJnP6QQh5ACH9EjIaoA9mA9_YP5OMbJBNtTUF5AdCWR6mm_23MDz5hYMQHvR3P1KGswBoM72OzLwH43hIrperREsaIRsL86S1xn1VvzxTUPT.Kdf4Yc_G0iLd6zbyamzKURWUjvrRvlm7kPR0uDfJjiUq82qkQW7LvwsTTMXbz4k75GUz8XAqwv.qVAKnbbZeD7ND3Zz8uH8Z0u9PwIAinlHhJTkSbZZY7jC.xPU3pb6BO9vjiv58c7Bf35CzdzYCUTq1U5esaNK97jeFMjpBHyufXf9mrxs38QZdkyxbLBe1w_BzSy48v1R8FDlvpEPFV8u0KTZbF9pZLc5s0jzqnPs3OdhCngOeC9rnedUKqMMQgX7pKRmsSVxPUfaOsX1pI7iNWN.aPnLA0qILBXNIlLiEJv2FFu5qZPaknUZj4.Q3XjRCVtvwoft.vVg6.CowGWEycj2m6hCn0BP1E9GKcMLKEqH7NJ1zg6zb3rLKOMGHGoTEDPrSvMUTWXH6WiRUXFN0TPRqZ0ITBxP_Z57_fmfJec5dtFbpWdhlaSF9DiYf7DdMlTEqRv98HCGF0GM6vnW2mjfJRewEimljs__dLz8m4goWTLn6nScYGGJjtTHS5dEGC7vOApvA9XD9FquQDCngmG.RrEVCSlRnSiOAU5bumN1uvc7uMAo6d2GCiKY7qhrAUGaFKD.iGN6pMMa6OlwUVKOHnQ6eGmEUbERmSS7PWDaI8lxkBHxxC011z1aixjqPgOC3JTX2XSVGEei3Sn1VeTJ14BeC4tmtECk0OHBn2SW4MahdkQ2HY2vSiDQ6Ane3qRn3MOjVaKfyF1ICN_IeiG6r8AXm9dquXoihNdgdGDZl6DmDVsQIkr4woijA3Wgl_mP9pIvkTNxGeQGt0qy3Hm36.iDeA6Zw_1pfa24LVGSHT_mz8ydKB6gMKB6VlaNwM6TvvNmQ3_flEXYg7Ij4wSrRnQdWUAlCPGN_9GOVu4cH43M43wo_Rf.J9KimluZ5Ky2ZTB8QVshyi9cRhXiZ2zDl7YRdbiGZ0Jwy5gSutXR2eRGrfSd02pcwB8P4FfaUsPCugfiLQlfVvcczJ3W0oxn21oqvu2haliI5E1tfMyRKGYBBJvEGd7vd6XHhQCXIb2E.CyxTs3fpJJw40PslIKgIxb2.XUX23xU4bQmUH9ni7CaH35Axi9D"};var cpo = document.createElement('script');cpo.src = '/cdn-cgi/challenge-platform/h/b/orchestrate/chl_page/v1?ray=92de17264c48fe8e';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, "\/classification\/?__cf_chl_rt_tk=v1tmd5Yrpuec4cyEFOVlcf20w1NymokzLybrOzc5_Lg-1744244552-1.0.1.1-NqPe_MzET0fdILV0Nyefp_cmSsS3XhEs6GeZ8LBElk8" + window._cf_chl_opt.cOgUHash);cpo.onload = function() {history.replaceState(null, null, ogU);}}document.getElementsByTagName('head')[0].appendChild(cpo);}());</script></body></html>