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: '92d610ebfc3b879f',cH: 'TzeijdpXBasTtU4upv76EQkWzIulmUhpNG0.jl5Kdws-1744160411-1.2.1.1-GxCi9DMtu4CVDGZtcDEk_IlZC6g4XmXpBgpjhWjCn3_JqXR4SVIDgxPVhPkuQemh',cUPMDTk: "\/1320.93061?__cf_chl_tk=3ay67PbUwBPAFJrZMyo13iprnRzvSFrIZ_L1H4NfePo-1744160411-1.0.1.1-f3x5jWj1b1zmSiBu1Y9gior_JM2xsoJkYOf4QR0lXnY",cFPWv: 'g',cITimeS: '1744160411',cTTimeMs: '1000',cMTimeMs: '390000',cTplC: 0,cTplV: 5,cTplB: 'cf',cK: "unsupported_browser_beacon",fa: "\/1320.93061?__cf_chl_f_tk=3ay67PbUwBPAFJrZMyo13iprnRzvSFrIZ_L1H4NfePo-1744160411-1.0.1.1-f3x5jWj1b1zmSiBu1Y9gior_JM2xsoJkYOf4QR0lXnY",md: "rNqb4XAFcSOiNYMEKAkqZudWfyeTVS3BDDHrJE_YLhA-1744160411-1.2.1.1-357UECexqdD.NfODPmChU7XUoolTmymBl6xK.2wg0aNVwOwKxcvgUvTgy4cu8mG0RLVrxZosK5kPs80PIm350ePHZkL4k5q4XesMRnoJVrxD2wH1cbQdWFFfpNzXhVNDlQjqPODYLm2NJwyuD6adNMLjygG6YJHsx3dzf0csFs3d71vaXGwBKV4Wog8LvqfgUozghr0LOiMzmk4OZoQpW.C6elLGsrRvVDgysmvp2SU94Z7ieeozkm3MpsWleG.VaeEsAadAinCoIweR1gT.FTsyKQ5DjAg9a22DvqfXwvwtNVShzcKSxU4U4PpR94Mt1hg7LCYiWTEsZOeEqV5YZORGFVnJLq88LX131SnRWWE5zjYPiW7t1CFCWgaYKnRYJz.zhQTW9M.B0NK8DKVNFORrBxaB.N2.UjODXXgpjW8tDGTEQqzSakHVGL6SoXcMPDATgPtXasJLC3x2xxJKzMKhh5AGjxC1yZ9WF3x1QaReHWN3V8rPJuJj5UEGhBI2AS1tYK8I.Ucz1b.n0bR4.PfB0uWVzvjFEY7UBF6Tbf4e4_Pnf2pew.AXcC3fKmK3mG2hvOfxWzDUkDJ2BinhlwVWdOuDv._4SAxqdI1y2q0BVdKqVyhQM2ehcWuBGS64hFAtNpWQFrNAG7jpDKGvnOus.tmgQZ5wkZTUvG9Qj5nyJWgf_qrL.36QDnqQ77eYnVd_e6KzqK61adT4diqbA7gidk.oL8kfM5CC6vXeJT1wyF9KSj69duw4a6l7yRzp_KPya9IGFVKtteBAPhUGY1GD_JaMtcXQ1ptX49P3qJnwmMJHKio7INecC_1Zq1eB7wlOsqQTm_zsDUsUj0D97UW7qsd1LwI0ovDmI0zggGPEIGOBGBdNYRIF5P_y3urA5H5.V79kjNk.oPVU206nO3a_gkZXPE3l6SkfbbaMymNDSlNlMbZRa76VLQBEpUcOLzC.nYNZxOjUJxjIbJmkFbX3lgYWOs_YmwUoCKvtfY2jQU2exnfyyvakGkNEIZOVHXt5NLhbyLOlUQoC9LIDJNAVj8MX001rODq23Qx0IysXJ7pzcgmx3MpkyFqpBm2g8FlAniZw13Qkk5qRtCsFhD_a1qwBuTHx4Z8IoKn.jtvI0lunoY7s.teK_t.8oX3Xj5vaERDOwMbaj97Gryvk92ZZZFTuXjxwWBklvRwISI2FZnMMs4vzUYjU74tUvRXl",mdrd: "pW8Vq6mxDeGaMdBWb8M2uDXLy8aIlpUocaYZfBimFOI-1744160411-1.2.1.1-86ZvF8fXplXfW5byi.ONiCoOwyLqW1atcflyv968yPVvPxRAJqphwEno_C4VpJQmxGu1hppxHbE1mN5uTIhmBU.QYabeo6lYnDLJiHsjjxZWftsdp7hw8GYW1mXfR3llHRdKqQfb9P_uS8851Dre5H5_LHnwU8.XxTWjFQMrGxhmxg6Ris4xnHLNpjmR6qfkcpDPKRA2pKXoumtVVhQas5co11PexNdM3BSggznDk_bRmbKKrCHH.c309XEqTxHb_r4qPdWHCvXuuYKpvwL3F3Yt.F7_5JiMMDNwDqO2Wj8AM9Mvp4D5IeRqYFhL3DUmug.O_kxcxn9z2OU5aBG5lr_OCmh67hlCMjrUkhPJ4KPRhVV3q7TYd0tK68QSEyH.grT5ezLTGDc0KtygZ1XkLiDzcXNrozjYYlhYou7J.z8ytD81I_OyKY.aZRaxUk8avdk.GQisJyNbkUhNQb7ZEO5qpJ9XSGjoAbL8sJzE9ecEdLsy6GzAHdkpxn3MXTUDDsKdvgOTqvNHds2EDCC.SaFpdUrUjiPw.MX8XAfgDe3kXJ__1lFx7DmEZsNSxaMHldyze9HEHTq4k0ymsF1Uogm0CNDISgfCbTOPzBILAadCYUPARP2lBEaiZFZIv7lTJke7LVfLnsWF7G761OHqk7fnd3u7ssUo30kHgR92HWafseKvvsedjme3MuUG5Zs8X5r4NsG50yMhsQJ16qgi9D_Q7.XNc9yZuthkdQADFOEYhBitgAiE9Vbsj6mSuzP2R.QYxwxWJhMc7vP40nQcUR6BQZhIswC3t4ZcyMqKk.weCVy7M9Y6G1e0AF1lq.DzgYzK132rlLbhMjuKZ14HBv5xEL5aIDm4R88ifldF2yShHe8bGg.WuNpsTzZX26YXnIQ2hF3wq5CbbFN3csIgFx.jIMsLm0LB.hSk5SI_dFG_PTjewNTfO6jilGvuKlDAqusiclZoDjU8sG6KeGDjZ9kKABng0NK6ftQKJw_gEC.AsbNlpugHhrqmFLjQrEpzbAtMbjacylwsG15yhMRkkhFk8tlLHJVSv7vaKUtdNW0r4I7hNhrDN0MSoD597D6rD5eVQGX4Cc.QtqgDh7wOLzhhnn.EHYmr6sVHkOUf5wqYfTXSVIP.uAUQlAGxJPRpi8UnWhPr7MkXs0bYINH1jOp7dJLVqKcX2yDINExkSY7EbFh5.4zp0A.XcUE8LHzrqmfC6w.CN1hd40TsbeeTJi9IkkO7yaQQxHHVKrS4OAlAvcuNDVt5sFViv_zOWZ8CHJi2txaQR9NAWUvUg.BOou3XhVnRGwWirIa6SsxkmsiL3uSfKvoIMoc8S0MEM3fc0xDaR40XD.vvu8o9t7EWWnk1_qR6hzNASptm6Ic0QqiLF7FsfNYkVtteZscMdOt0g8R0V9VUXUtTdh6KjoZ_0oNVMNwj1CFJYNy5NtuqUL57uUv.HYTax4OCKkIze69YirPXzhc9x2755x7sP2Adj8Q0xQUjwLgj7OcZzzjlYiDrAYr7mqGgULZ.9NGDWtVqzYukb8zi3ZfYDTZIJunaXxMvziNHJ6d5Wju8GkAf.YibPLOSH0ooKvlZ9sjBH4EmwuMHTvp4BS9dTErYrhY1qgZPlCf7mAb2yUPpH19pZRLWU7i88WlurpML8spSl.KplJuXu6eeapApTJ_Mjs4gayYcWMTUjuMh4MKqJ1SgWH0LKqRuy4w7QlnNSMQ0EEKoub2G_oozNiGNZMk.aMCoCRwollDKeVRMbSs4F3Ii2OrFP3Q1Py4jK7Cyn_RMqnoaWOJITxrQzHJ2FLe1ZnYbFkX2M_LNcORSy7gDGZKgGPMMKOwaBMREapXtYgsueRDsf7X6KQxpKd.BVXBF_aZDfjnQRfzVCZyhqnNOAgI7AK7Kw3dKr4eiPHhGEz07Atl6mB1wAfQEE29lZCe6xgRmDUJngqxO6sGeOuPjHBHdp5E1Z4TUMzu0Ng68u.Pz97L7tZH2eNxUgp9e9iRXKTUFIiqgQ3ge1R7sm5BUbS6rWzXHnN06eegN4SFZTK4Qem6Q"};var cpo = document.createElement('script');cpo.src = '/cdn-cgi/challenge-platform/h/g/orchestrate/chl_page/v1?ray=92d610ebfc3b879f';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, "\/1320.93061?__cf_chl_rt_tk=3ay67PbUwBPAFJrZMyo13iprnRzvSFrIZ_L1H4NfePo-1744160411-1.0.1.1-f3x5jWj1b1zmSiBu1Y9gior_JM2xsoJkYOf4QR0lXnY" + window._cf_chl_opt.cOgUHash);cpo.onload = function() {history.replaceState(null, null, ogU);}}document.getElementsByTagName('head')[0].appendChild(cpo);}());</script></body></html>