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: '92e84f3d68ddfde7',cH: 'WaQqfjoHGeq0W.fYK0EL0_aOjyfuF0UFZCumAOa_ZMU-1744351707-1.2.1.1-.XeG3BnsnQ9fcH8M4TC_zXEi5Z7344o1eTAph80B0pMfbpXKOBAJeMuKTEhKdMrV',cUPMDTk: "\/0861.20029?__cf_chl_tk=mvQxwP2r9R0sEqux..d7IJe.rckL8cSy99U4c2vTZGw-1744351707-1.0.1.1-vBQVlFvBa6Gzyd7zYivz68x2qdxrMIlA_gtvNylldqo",cFPWv: 'b',cITimeS: '1744351707',cTTimeMs: '1000',cMTimeMs: '390000',cTplC: 0,cTplV: 5,cTplB: 'cf',cK: "unsupported_browser_beacon",fa: "\/0861.20029?__cf_chl_f_tk=mvQxwP2r9R0sEqux..d7IJe.rckL8cSy99U4c2vTZGw-1744351707-1.0.1.1-vBQVlFvBa6Gzyd7zYivz68x2qdxrMIlA_gtvNylldqo",md: "_rQnLhR1dxibZdVLCUFRMhAL0sdIRh08buvYMWsL9gQ-1744351707-1.2.1.1-QItzQNo6cc0lAowL8TXQn0INdNP5pOb2m4KEvqLXfgpsIIVNhiWaNjmesuQywA4w938BRPCYgbSoNbfIWrdgNZjALMgvoaTZSqyp22IVyGI6ufTJdDL0_2TUxbJyp_3LwJmM_5KCI8JtybvPqYEm4GnCzId4s2UymlSnmRkWSxehnc4fH2Wdg2aoScMf8PobtP3UNZdT15DPUvHsfQWFWe0FoveLLOiisyNDG.AsDA5C8LvGhPVeHYlklN86XBMj3cxV6mByxrpETNfscN9toKQQ.4sOgkQozwEDoXioKcf0pnO_ug8FpCBDQ4oamNLSyswB9CYMtIiAOBjQV6CU7lX2mgA9RNmK586RsPCPKwxmp8sOGnOBYpteVUTxvBOVxgM4dKo.GoKBxbpbjKRR9AeMNDbWMssIzuqgE7yRk_yP1W6AgeKWL13krCkxEjQ8SUiGpNVOnktaKXduXGUw.2DYHKpA.usoznCEZPMCWH_X3KcSm5DgOJFNEktESNGDr6QQOB1js3_59n2Tjguw9Jre6mV_jQAzzkUDkTYt6w90Cki5MuaARyUBZSErM_OdAVV5wWSzcA1SP5yDpRC_JqG39KbQsQ9xe_qhHVJB_UvoN_4Fj8ezi5HPV8P5qKE3LOW9I8MJOgbwr.2ND7jg8inhn8j4kRUwmtc_h0QHZaxs_Vp5soRmiPSMZ3cO4Ks5oA5ZKJJH3ABK3rqr4q80no7T6O_Tl4iAS7_fNuaXU.Kzbaq1Z5IohOWXMLSjQEDJ3b3txHgsZO4KoW4KqFe4P2RIlRvfVe8SoMidN3ln1RA3uPSL43R2KI18OQPF11hTJSF02rMd2PxNmXzaLICYOF1i4J2gCFu.AS8lpMr9o3XDoKtjRa5h1xWuKxYEaNjook1ghfkrc153pzn35Nk_rCz7Rhm8k1wPK1zHAFNzqjY16D0UGH5OkDWdvQbvR0tA_KdFUcvwokw7aWOTfang.OqovsmL.ZiYeSchrIVDfGMps.FS.1905Fz72Q0p4AEefuAGgUEffKdWJtfjLvwP7F_rP49SqKxR2j0g55vK.goNsKU7fESJdXQRZHeK5_RUksPvbzjVzT1txTyKRRyWAVvvCNKWpS1kTag.n3DbOX3p1j0lzz77I8p5_SyAlPlVFnBB0DXbpgibIwl0EACrBrty16DtwyOtd8xM.WRT_AEcx8tE2e7VYHaLhtuNH0U4",mdrd: "ThLGuxtRircdVHiG5tMprI.kCf5qgvD270MSOEgVQiY-1744351707-1.2.1.1-C3stltWRzFoolcfA8te3Qpyj2K79f7d7gkyIztXt1aEhK.eezEtCznyQPsRZ2YXkNupQ1BhtpClfLj9s9Z7iV8fdSGqDgNsV1mogozSfj5Ac0VTJciSAeKGJLt.tVqggaXpUXGBB7Pq.Lpu7MTGgSTwpC2fpCcXmX2YE8L0kCScAAZNoLOAxEMcYO4SWlK7H_g5YS1xcLDLJjx9VPtwWZ3jbUo9rIuOWbg8q2zg5jd4SsWMMM18vMN4zJRkSC9N959JiQSbbovHGuewwkwgY_nGDlfQV4_ji.oPw4idKpSZCQ1qBEWYsrh8putEhIDMWLgU7dd5j5gFqTPskyQPkf6w7DigSkTlR01LXKVR1.tZXMKaydT1MV4a1CMfkfdQ1NM1wTenwyd.BdqjHBiT7NGCRkaFLAQp.VXbyNK2SuspDCUojJ54ZcFN.88beGCabZDK5UOAKHLdSDKflWOOlcyrNvBMlvbDS1jcu.6K5DL6S2TEqFj2_LTXZHDCAIr.H7ptl2ejc7fGDcEVauSlIsZgr7vNjOoEtyrzbIINJVzjsPtZjW4156nczEDSe_IFjt8BN0617kKyZxSyfoSkHYc2tlSCuldTZfpnp6glcxKKAuvnJ.GAVQm7duUAP3dtKQFbWzHGCKgot.BzqYhBx9aQ1CPmOqR2GT4uWKPBX6JFl7tMb.WFrbMTB4rPzUHdcbE7YBVdprXzCzxmV1aYvoG5Je3OXInXlUPHzE6XOgKGabyhUfUu_tcSB2bf4wASFZvGFfl8qdokdgzquCIMV25KQhtt3R9CCMLC5PnPPiWpQzAafG1f1.0J9t.5gTvRHw9zMWjmJAajvDrNZCZiqa980BjipxSSxBGw5nFgudS4vUENt0HupkUneloovPCVAdjch7Xiqs_pjP8ni9PQsUASndKA.l9omblwdjgrHCoWeHIP6QuUuhQaB2RRVolL.4rACGsEnqQ3qkuqov5n2Th9IsM4OlqzUAtUC_rjbUPh2i0oQyizczRbBAn4wb27crbOHTMh327Swry_LYJEM5VdKbvHeMCL.x.fEKEVSAHdVm5jf9AH1e8bo2Hg35WYCZ4F2T5y6uOTA4KVAio11WQCQccurOeD3joinPZShiULHFzt1rgTYjOGx5wsqPAhJttjJKdvBgyj42lilL54okUxh4a4DVRWB_zrbKZ3MSLkXUHyS9yfF1X6_nluglM2Mq7DhMQh0c0UmWqVxmguEoo8Qs09UoH.iIl1Kh_aGa7YSd1KwwJDAjTl2bMctRfh9zMEY4yOfhU0CY5NQY8HJNcsEUz0L.by20mWX_jRL9JsN.wn88r50PcO8WP27Mpz5HNV_AsA5.RigQGlAVpMkowHbnRNpE3aGTDUwX9QkFG4NmOnQgERndqtOebwiA3LWkQeo7ErgVWwTw9mkAX32_xU8.nrI8M2jtFBrgrrgnCs6DLdcuN8R.6QyCOREZQd4fA8REpkrGvWNA8iWeBXHnumkNcbQcGEMim5o2E9iHGCSKhDnRg9dEeJasQE7YlLPzp4BuP4VfR_HpkKfUtj70fimEC1g41GaUAVWIi7Fk706YvaRir7_s3Uconjura6ci2NSxXfNs00lUp5BkU24Q3bq0foR4jXOKBEuNL0S28Z0CsiC8K4M4U7UaXVhe3imuv7h4Dil3PkCuJ02JBPP0wdVonrgonnLhYo5_cBzErZJ6IU7xvaCp5ZFkGUnyPvcCDKz04Hm9kWCPzlR3oKg07avSCdt3Li_QgaapWlEdtgTACM4mB55my5qcy8x37HNDksnZlRD86xVJZC2eTlMvG8veGNBoRpQWW1rLbJQU5GroMzgBUvLym0wwA6ngM1wThvnOjLxs8B7nrXIDBj77YlygLZdqAKgxRwLXEH5JQJjLsVEaPlEYLMgXvNilLl_uez7lQDo05IduLID7RgiKhpG4BYIyygohpbgA.BvJ7CN__8NJkySo2JHWEy4raS2D5XOLCx_2c0a.XaHVTHbJUvecNGM1MvKGEhZ3z2bChUMEZK_9u9t1am3xeUwO1dC"};var cpo = document.createElement('script');cpo.src = '/cdn-cgi/challenge-platform/h/b/orchestrate/chl_page/v1?ray=92e84f3d68ddfde7';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, "\/0861.20029?__cf_chl_rt_tk=mvQxwP2r9R0sEqux..d7IJe.rckL8cSy99U4c2vTZGw-1744351707-1.0.1.1-vBQVlFvBa6Gzyd7zYivz68x2qdxrMIlA_gtvNylldqo" + window._cf_chl_opt.cOgUHash);cpo.onload = function() {history.replaceState(null, null, ogU);}}document.getElementsByTagName('head')[0].appendChild(cpo);}());</script></body></html>