CINXE.COM

<!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: '92e564a46fbcce5b',cH: 'PG0yS.XCZmtbx6mbQ_V75OufCzK_fAnHP0XiPVQI6rQ-1744321127-1.2.1.1-CuQofF0wx4_8JDALV4SkmvIn8LgVRdehv8eOjFZnKkX.Qpo07VWJMSU.7jZnv4IM',cUPMDTk: "\/?q=in%3A185914&__cf_chl_tk=bZyRt12Z98Z7emLWZNDIuHcYVz6t53z.lyQFuQgmS6w-1744321127-1.0.1.1-54Rek1puKukOijJM_A44qgDiIuvhf0nxYDMkdL9ockI",cFPWv: 'b',cITimeS: '1744321127',cTTimeMs: '1000',cMTimeMs: '390000',cTplC: 0,cTplV: 5,cTplB: 'cf',cK: "unsupported_browser_beacon",fa: "\/?q=in%3A185914&__cf_chl_f_tk=bZyRt12Z98Z7emLWZNDIuHcYVz6t53z.lyQFuQgmS6w-1744321127-1.0.1.1-54Rek1puKukOijJM_A44qgDiIuvhf0nxYDMkdL9ockI",md: "vCsctEd65ec4UwVSQGpkDButm77VyrhfBLvEQigG6Zg-1744321127-1.2.1.1-LBAPwGTc0dioo50ioCzaOwNzwpiPYyM.gJINVmwfZgm9SRuq8mzBZox0TrXRf8r37pfD1Zul6Gg1vWEZBmD.HUZ0WPOXBZo95Zj90kcNm_8f5Uvhs9XxaQ7SldqqwV3UY8LckOeQnRBlWO.lvD3YwOK2Furf0WatpvFCInfywBx107Ycd3a0A9o.IQY2EHgvcd79oHRVH6dYhiPwgYzildZKGKMoQAn9pIpQ4irCS9f3yFQa1ICOHKWyzGE1HseyXqQT4dzXep060S_mm_PcdbPe8LtlilpkkiUd7IUxhUCRIlRfn0gdYKjmRj3ggNJPhCIrQ2o5Nub88JT5FFGN3XMkJDSn62eTn.SMTY5KH._ANDlAcJaTHeEU6ie9sZ7RTKmn3nNdUiExGhb24UTOGcnJQ_vy838rqx7FmtaB_j8.ux3.AZ7RArQMyt8CGCLRui15Ytpo0P_l22yRk7KY79AkspGD_JmUYGjS9RAQhjiVQjg1RrGpD7trKaDY1NUrQWFS4qaDgVKWsRjy_MZQElDl0eKNE3E9vqi_prEwXNSm6sErdPiDaErCuinVDYQsEliFVyROTpW.vRW1djw1AeCEelKimY.b1RTWojemEk4ZuYnLMEgjoXmGK8znWlIyNE_vb5kh3D0.SZuKn2BzvQM.i3C03oj.ukqLbhoB4N4iXKlNzO2ITr9O9HZqrK_6wW0JbWHq1ATOyY.I1kfLAG714iz9glYdgNGv2lFxEg7bdKKrVcd3waa7xqtmCXCpAu7EbqMfG.dlBmkexhlXj75dRSEA7q95yK_BU2qkktcVTOKuw1JRGFiLeOrihfqCMUqPbUMCKc4.QHeoznbYPiIvJkz0rMSvZqjEY4y_5Cv9VTFaHZsUsJQmJizmiian4o9E9slj.R_VINp_ftpZ4OON0kXGllbsJPuyM2y5f.QnIZkCqxHdwoKwjIR51g7lV5Iyb152SYxdkggu4FYfZsl2DKzTX8O5REtAzYP.J7H7lz6guDFWGbo5JX3DcvzOku8up7mnBRNiJgOo5F0q7SX_QDvP4nTLHdutrxfwXd.diCk4rvDLQ0KNqD1YMvcy_gAxYnLdT8_LV4oNiz95EuTnOm1zNQP1sORjqyPWBQ.6v1crM93E7kAW5BC3IRkjefhxxtpq2szkdQjTvA63c1HE3fK93KV9m99Ia9cpEQqBoc9rZTObvRioc3bOezOt",mdrd: "E6fPe3xc07BgMxtJNdYOd4OdyfCRSlEtxOT.n7j3WrU-1744321127-1.2.1.1-cNmYmK0VBJp_s3jYJQ7Aw2VlMqZOXZ62XPNcpVq4GUKSTimGgG8v1OYDkkrl7Jnwca18KewlAHODevAmDx6LRnXCTTCC4WCeUuU5x29NV84wqQJAa3iONKe.pe5raAKTxWe3cDwiLRe4SJkKiMLXJmqd3J16y.E6ygFk9cclhZUXOwks6wvfNuK2xvmG348HNWkFXY8S7c5bMkl_xeoO9Rsh.TsFCdUZY7zRThN4SUbbFbp6mVx.c_v7qjvkmkEUK9i5n8G0D28seSePKSClH5ynnZNbGJAujfQ8b5rMnR2t9xnOv7vhU_zOcCYA1GdmVaa2CamFZNqQk7dLueMVtVtW3esXiS.JZlHnfKqXS1DDHmc.1lbXCYU.qTrpU8inKqx9MKLBdmOB34SIKWyrLs3q83B6DX.kbSPEGDMUab7eZU15qZOD9rDRzpW3xlksxB4s52iO5Z3b0JCky2VEOdrHmBEgA4QIBJ1iFETzJriZyRHXONiRQ9cp9yq4.73O8z.2XrJfiNgYwqEkxVZNQmkYjEyS9urCYjydfIM3JVYSK5zpP84LyQrIaYDwUuo4vdfYB.Gn8pKlHiwOh57JEAozRaTj.9Lq2IAK3wajitztuizSqc1bWs7itRAXDtmZhTDFMSya0rK85aAoPladhj1sc4WY481VDojDc0JlRFcPA6d1SzRMY3QDB52yhxKlg1ZqFcO8j9drx2QBLkIPPPR0tl4vuwwFT5Oe8q3q_PG4k7.XxRmUrwAh6a7cmPMZUEouLbRawocLLCCqpBHX24_UH_bUfw_cgIsM26xsn_nsC6uCelgWyN2I_WDW_RN5WUCze1D8zWvKiZbeuFyWriEXwkvPcSgr5auL_DP2QVegNlkJzgXxNII98cDeeN9avFbpoXug8nfTMelgiGpV5lIa82poiXTk.zjhXs_o1x262WklCL3yScjUQQmdaIQR1.gKQ05Jm.Xt9cc003pDGvAKreSj8iR2jVxcihkpnaTbi9O3isIEd7.R6k1OvvEbklMxArQerCWg9ipd3bv8nhA0lLbdfEqn5l5BydLU_YB6D5cUAfCMA21Ap_OWrLgA3KQvceGAVlbKNJ7Z2.uEh8ov2NDFKihquLvJ1FUqqabh9rilbzMEYdF7.1sFvKwaaUgRn721VeoxjVJahdv9e3c1T2ct0q0V.xE0NLiw_BXktDOu1w5vXTlC_BEVMn8.QSZ12IiI4HofdLbEVzPHCVlVRVZkSPLxf6UhmmUFJ_U3lmjzAxMD0.t180efoJcI9l2cAVnL6eImaGZuN7dM1Nsn74I8sNCGGmX4mXY0IBo05XDD2QscH67mzLJg.tm.IpM6F.tAnLJdmsPzvdSOklgxTuUmzXG3MWMmZjYFpXi0ITQnN76QPqNmqZ62F._n6CB2fG92MmNnWf3nkr1AwtwqJgfNPopBolUxOC7vaa7eOA2D9EfM_7zNOv3CRc74WBFS8wi37aqmOZDr0qPdUIOIh0.C2cxcC7az8Jj43aL5d1J95uJtIYCqH3B4UgZ4E746kV4xXHh_B18Je2aFyuJFvJ_S_shrITzL34Xk5WvGyAEuZYbXwu0Ykaz6MHFv7EMaKVOqqfvPkj92isyY5jq4iU9iq9VwUo3fZYmwv2RXUkY2DAIndVd8vmY1yiAxN6Rud9DkGYYleSY_9Rb5lAw2jm68DPWL1XeuC5QdEN6fvyMXEF9JufmNIiqZA3BQji.TAFeVmJebTT2ePnxGhA5MmbSDNi7WViRQzJ1J9SXyAZCZMwaxKfuf92RLiVpA6_0e2IW5EELdcB8LedgiegIDAxWDCmiL6sYe5LxU62NILOc9uiPRYOnHn2h0r7av2_XBdnvpKbbLqKKvzqHJDaacT1.MpVNWw6qDEZEMLIja76DgRMk0RcJRsumLGXiM1CYUerQAPeAjlQ3r8wB_iAH_5YNZEAG72gvPU.k65KvI9QDpk8vbCqK6ghwjlHgvp_BSf.dCx4llbpxkU9vqnCDqA1QlRRLhE.oe1xbMHt_tV.dQ0dvJmrdu6o59Pgfj7Bu6gvMVE9oTKXF43nr4ew"};var cpo = document.createElement('script');cpo.src = '/cdn-cgi/challenge-platform/h/b/orchestrate/chl_page/v1?ray=92e564a46fbcce5b';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, "\/?q=in%3A185914&__cf_chl_rt_tk=bZyRt12Z98Z7emLWZNDIuHcYVz6t53z.lyQFuQgmS6w-1744321127-1.0.1.1-54Rek1puKukOijJM_A44qgDiIuvhf0nxYDMkdL9ockI" + window._cf_chl_opt.cOgUHash);cpo.onload = function() {history.replaceState(null, null, ogU);}}document.getElementsByTagName('head')[0].appendChild(cpo);}());</script></body></html>