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: '92d9e35f3d37f8de',cH: 'CFGOZT0sxVcbAkdK6sE7Kc.0bEQMnCvh6W7_LezYVFU-1744200488-1.2.1.1-FiA1rC_zXF2237l6wyJdv2Wg.4BbQ6uc7w26S3MCj1b.rHriNQOmcYOcZAMzo0jR',cUPMDTk: "\/0642.62016?__cf_chl_tk=eACSEu4IkjN7nCGQuRsqsjrJx_ywAYDytHkALdYZ4I8-1744200488-1.0.1.1-U.pZirNgsPjJnblVnLKNMkeapfFiLHK50DjaUyr1xB0",cFPWv: 'g',cITimeS: '1744200488',cTTimeMs: '1000',cMTimeMs: '390000',cTplC: 0,cTplV: 5,cTplB: 'cf',cK: "unsupported_browser_beacon",fa: "\/0642.62016?__cf_chl_f_tk=eACSEu4IkjN7nCGQuRsqsjrJx_ywAYDytHkALdYZ4I8-1744200488-1.0.1.1-U.pZirNgsPjJnblVnLKNMkeapfFiLHK50DjaUyr1xB0",md: "MzTC7dTup.QHcTEzhWuxUfzI91UpVCYDCFigFkhrqSk-1744200488-1.2.1.1-xDBoWyQW03l70xEqoMsLqUEn.EyFA.1oQnMo6VHpAABDj8cyMF177AFKz72QXKgEtEaZBXTmQ7pKVlcpBneBPOF0UAhV_cNOIIxeaQO9l_1x0su3oojO7Y5hAalo_qPDi5Lb2YXr9siLonrLjRG0EsshV8SV0jWldX80SWjSsb32uVsc_00G_A7smVPf3fUOd3kfDy9ZTaYRWklQaem1nJAt5x3TTIVcTxd2WYp3LAwnaoBq_TTQ2Q_unh2Tk0AKx2En14hWNzZFZBrqCMH.D_DlQ6UOxPn2tQ0n3gLg.P9ZmzHleqeduAjV4_JAsJk8gXmRDrFle9oFEn3A40hI.Hs1Bl3OB36zqPUeBosdAx0yCVSHPAg2P4BmreTs5XA_Swx7tOdTCQ.6yK.ANF21m2Qjs1yXY_tuya38GXu3i052.YsOtV1XRKJ2Urw4752bTuXTw4iZtKdKWGeMoqNym4VWAuVHtj25WUM60eMlIhjfNaTkrcQLkVLudN6yPoP94ijc9AFRYrgG4MWi_8ZYlvq3PF7rskP1emt0yq.vZu1cx2sMpLrHlIVZgINeE1lUkR8xux8q_ckcxsmYR_J3cD2iqlBgaWZ.1osFST9UVMzYOetewionOskAewbmyBHtkoWYLfl7EwNNZHNhr1CGc0qLBqvbsyiZJSrUH0dLksyqfzIE.spRu9xpEu88CEEqNOIHhAdeYDo4i3kQynGuLt9fupxrzpTN7oXrtFYiE8gjVYaHNXHr75aiDuVL043PSvVXK2A6NADfZYcLuPA4kHtL3s8_o.ka8Y6iUBEvsGChNplioos_DVu6igxPuYih3VwQ4fWwBVlEdnoQi7Y7VsxF2wyC0dg_iG7l45Al44a5N4KMYbKeEANNM2FF9wG2tUHY.qRdSUY.d..BytRXUAnL_rkR0_TRcRgd_MKmTwCLY0TMkRRIpdDq9yzNIKPONmgW6zdf6MpxO8xzjdd5qL.529hP_RcvrbHiZPfANRlRseV3dKze2PYVUjGmvZI7Kc8biDTXK7Fig7FDtrzTKqgjMDP9Ai2kWO4V_swaflr2h7e5ZSFxszowjvu2ED4.rzFx4ldjQkKG7E91I.RXaFHcx3NPSt6t.C4NTbqoe94BNojxoYrYLOYYl257FqBuiNkZgBAPAil0UT8iPPesyzLwfRkqB8CsadP0iEiyXi39Be8NOuqncTudo3pPiYIk",mdrd: "hVct1h5uPfG2Nr80Vjyq.nKDqr_GBufwcBsDRIwYBtA-1744200488-1.2.1.1-VbU8eeJ.JOHs4i2Ds5_qqrQFbVTTolrKLmfNSc5aMBEYxSsrNGJ3O.cm8tLV3hMje31_HUdKNnj1GKhIfgrpg1UqvojLcF8g9gaDcwRP5hzFUgyH.lIeYf7KUW8DzHRUeIVRMPtQbauu26hMvqLtBNXLI9litsg43d6IbdyEk7mzI6guXbWKtqgWLM6iClK.H4IXskO24jPBl6ylV33lhhazfJ5bahI_ZXwmy4Uu.Pp2U3xOOeD4gp.uw6O54s9MJjbgJtBOxa5ox00E.ICC4J2cYWZvm9.WrgiujUcdp3rDGFwCwUNFDj.akAu0g3t1UXobhiGNnFzdG1_owqo4Va8G3TVDF.LCnynkapwPuRhH7MB0RMTDFp68slTwCTqnuPvAsuMF8tgiaGNIHt7LjtgUkCSVPxDsTQAtsS7R0W.ssTwnxY88G2nExpOaO_nIaWTS_RU.mabLBni1QbUorbfyN2j9wAB2kQ.q8rNS0osmcxm0pWjT4yvYK0eFu5L3U5pA7PLMyI.rOKC0.fXws5qfzrqN_qxCd_WJmF1a7LtB_S1vcIULVRolVgdYRmCRcSCcA_FyZI3TfznV1iJWML4C44mkCwUMD1Z3p_gjIFOA0SyJ1Jt4.HinOtBivuU.4hQYFtEK.tB.xIZ8Wv8emG9x5klwhyiJRMq5uFaFFTHZmDPj6kqYrr5Hs7VI3xI2qYxD__iKDtXDquGcTvjg4j0VoKe8MqpZlsxsfZiKAXSe4HRh_fIYky8LZkMiUOG2E45u.8Rf7fKOd3fBsAoQM0JA9Y_851CINSQstTXga0zya1U_sDzjRsGqGfFtKfj0r8va6lRKP1aLgyeqsGKTopLLA.ZopMfhEwktYJ6LowRVTR6wvu9SaBxBsjnXc1p6.ieD8vW.tZrak7hgy6duXKrQMtduOMdp8iafh1WjEnoO.K0D1gtQkHa7NKnZ.N2_s.vCRA4ZzM8SYHHwyP14vhSeB.6Z3RqteM5RP.kLJrARvp9SvwR70s_2SrssIcLOVx8viGWrrYCkGTZLd2SWb68nrj7U5yk0lJoCcgzqKZVakEcvDJhYMu6Zqser6sxC2xq_i1LK3Lk4BgibCPOOXCjEvwD0E9cKROyn88CjSvyBdvcSpe8i5jfbb.wxUW8fEMxFd85mjCcCc8OHyValQ_zlJ1_JpHbiG7SexYuwJt9018XcS7kfO2T.tWwyIAOCbuQAeuFl7ED4IZKPosFyb63KaVPHsJ_cWrCch3Ro5_NwZWoiRD1xA1FFA.RQv3y7aq6ySStEtqhTe7DjSaXFZdbbN.C4FyONVjrhLLftOs34gNc.vTf_S1AKV0TGFhB0dpa2F_mlnQfhZAAeD0WbaD8O7fZS7cEeCeQIi44.YrhHJ4pF_2lvLPxbiOg9YrEw6PF5UgpsWXW6yaT106W1LKjaCRHtuByQVrxPjQZSfxvtZJ4BHEPCI5qYJIC5MeAVkkQIlJ7byijCGStoyJ7TmiQjrXdF9mcf_8d9.2ZlMssWbQGb9XkPliZeQNDNG4Xkt3Scc5Q6Y9tic9oxTF3EMk8UV.IRF7tGBoY3V8C5uTtMx3fUdbGv.sWev5GRVvKldZVjvzCvARHuOeujyKdsbp1XWid9XnajEz3CwZbOsogjdHOIjrvR8cidypJtH52LxEL5Bhu9uCQMK2HV9ETVLqNN5qbD._lo1KrW759CYsmPO1R2PzejD1kTlGiTn6WItVI6cey8uFewNTO6PrDw65xDhJScjO0dy.TbdoBhTmZZPpOFijpEyZ0QuCxCRRRT1CaXs7teGvdAy2iCMOShbW5Cai0mkjq31jrUmFPW9nRHNrbVvzz0T_nc.MC17UybB_rOsUUYtzN95Ohcr9VPgujeM4XHWbj4GE5UW9sJv1NmJhbSyiLLVRDRvFDgev6RVXoxbxLQbOBpogD5QBGhvH587knpOuVXfwM9BKZN97P0dKnZ0sDO20gcoJWvGRr6ih.ti0WOHR31MWnu8S6kK4Zzuagd3FhWLVepqIKdjoaeIBjCMICx6eRZ1mQ598LV6SMSt_Fnz4Dl3tFlmogM6w"};var cpo = document.createElement('script');cpo.src = '/cdn-cgi/challenge-platform/h/g/orchestrate/chl_page/v1?ray=92d9e35f3d37f8de';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, "\/0642.62016?__cf_chl_rt_tk=eACSEu4IkjN7nCGQuRsqsjrJx_ywAYDytHkALdYZ4I8-1744200488-1.0.1.1-U.pZirNgsPjJnblVnLKNMkeapfFiLHK50DjaUyr1xB0" + window._cf_chl_opt.cOgUHash);cpo.onload = function() {history.replaceState(null, null, ogU);}}document.getElementsByTagName('head')[0].appendChild(cpo);}());</script></body></html>