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: '92dd98eec92e6015',cH: 'Y49YmNzd4uFvBhWRlk3mDD2DVYqKi0MuqOIsVAL8d7k-1744239382-1.2.1.1-LQFdbjmiAE_.FA0OaPfOxDKF.Y68DOIwaxZFh48VLSKs1WMLAjwVLFackhAaujDP',cUPMDTk: "\/1291.45001?__cf_chl_tk=4WbU.eTBoFdiYtJcuXz87rHwaUX0f6EFruElW7JPJZ4-1744239382-1.0.1.1-tFYy1vhc1PKmyq4q_DWe.llAalqOQmvbg1RmgROuXPY",cFPWv: 'b',cITimeS: '1744239382',cTTimeMs: '1000',cMTimeMs: '390000',cTplC: 0,cTplV: 5,cTplB: 'cf',cK: "unsupported_browser_beacon",fa: "\/1291.45001?__cf_chl_f_tk=4WbU.eTBoFdiYtJcuXz87rHwaUX0f6EFruElW7JPJZ4-1744239382-1.0.1.1-tFYy1vhc1PKmyq4q_DWe.llAalqOQmvbg1RmgROuXPY",md: "OT7BJv_Jl1YhOuVcGM9VN2naUgER9Bv4H_esHp7mCos-1744239382-1.2.1.1-puQkco_0LCIdOSzrhYT5a3f1ZrGSh2XlSCm._ftc5C6nUEQGkS4R5WUAuNCV1hnw_D8_QkrrZQ508MbJutGMaA_SWCPoZAmmlU_kCshiayTlQqphAV6r26yz0vt0JwNwQHi5wQ8uj2VYGHHto3czCWK6W3rQ2CqlOSwRouw8.8DqIiIryTg5io_ZXa.Og6kirlzu6uvT5K6bgkc7SRhJmJ9eaNk4v5qBvnNcyglb.g_AcdfoUy.aMdvlxzvtytBKvqTB48O8mgzu66VbX7C5xfMs.SKJRkLgcYqkWRwhA1osSG6PKCg.884lE4wTEsfDMvPpcnFDpqD_o_2pOEkVb8fHEPnntIAUIX.T4h2suaBcfufq__mxcWJWgLIjQW7_YQUYVfRpbAmPGSeoUpM8QhzWGR2bnHXJ04yGBhYVzjCQps62n33JqVpFi7GAk7qtawHGFCdjJaG8.JzIpweJN6Gsob1AZloks1v949PiBWgSkDHCkpJUjsCWUz6B5jg4G6KYeIYF1bYl4s4eSdg68IpwfKaM3jtGUd8XvmuBCVONa4ethMMYXCqW.wZz0CNGCv87R4pPlDHbbDg4bDtFAozv30MgZdT_4gFzAFclSX_rguhFQlzz81aTZVGUA1X6nF8UZZcYGCA37141SzlCNxeBysxdF_Trlb._98xgIMKhX6rkFcrAsg.lr7eBgB56zjzrWB.lZ3MDB0dxJ7rGihmUPEJXF9pPm_WxhQlDQuWtLL_x0U4T2rvx4LRzltN8uA3nsoQCuc5_ydDb1OPB8ZKNhAilQsjAhm59F7G0G78_n1oVFgzkhDKNAMCbJPZ4YsmYXrI8qBZCcIxG5ToxGhvq7rV32nRVhWUqzgIW.n7WrBjaBS9AcJDBpitdEVuE5YlV9isWsnmTV3w_NubJ9L0U6zwWQWDjcFwQLupORJaOjxYqoc4gQmdZRWnQ_Ct0HrBrPdHpzy3C.rFPFxgogJTMrgK8Lb4w2oLSn0HBng3c5c.x9GskDzJAfF5j7PjE5lX_az2mtJiaO_WUcjq726Q9WEajYqe1kc4tiyKnnUxkINxs5WJG0Zx.9J6BFR2xLcjaQFdhT71cIxKlDRG8FoXEVgZ19qS_DPLARdjG7oSOX2RmTZ4Z5mFC_lDCqQEwucgJ6dQMJmA.IWYMrc3q64oZIaxx60cfuH4hXd4P9FkevipKbBPl6N4wSUyMPUhG",mdrd: "75tLW8XOB1ut7vs1onCseL1GDM7lM2oIT8Cw1kGUFGc-1744239382-1.2.1.1-u2QnpM33EhYobD0YFvHWmzUJVviebcPty49ltOFJSfaT1zRgiuJ7o5Bt_BL7wc943oREBdEXAs80pCpx.hgbialFmzGSvruZAXoZYR3WmBQV6jfqpbPqNIAC_32BMtrME3TO07eZhkK5Jsc3uLxReXK0.XsKM6s3ERr3bQQ_S6MuCMNl5bihfTacKXakgNtdLnWx3XGUAPbTRQXB5F7mCe7kqfAUzWrVD7p5S7m1qweije7vpYyAqa_nFQ8wVbAwKX4QL91w2RUrEYlFVuJ5.vsN6MXbxwlrwlkQ0BIfmBanTfkJBpdJ17VxBHC7rhwzeT.1sz7pu_aTxfFfuTWWtvQJXDRPyJUVzv7O0m4Wi0unD54.gf3DzlzhOsbPHtxv70k58MRjOtcUDZbALJGM8kPjLtTLEIMyfl6N4gfyiEDvjN6yMbW2dXgSnXte_glXXibB1a4VLSpuLGOO08D40zm_rrvrY2eKLLcBKZp7THCtxy524CPfq_j6mhpUilEh6fjYFpiSKmk971rMd7rAxVvA6wGZnKBsYjCokRaOI0eXg6yCL_vBxT.FKtXf3FCtHmkXkiY0ZBtKcrzAhEONVmG_8n87ovGkn_wuBdO5l4bkTVC5rTcWrxUCfHYf8Rc7NSGpdSAjsA6.Z4B8vmJpj1FA7r_6n5YhdTOFVigzZbHP3gDa.ib6VEV9Rg5gKZ1RcZE31bNI5PBhRICqjQDVIH35w0H9L2crQVCgCRfdwLX53H3.tK_uAHZxoqvF1NnOIxeo6wvzoHgsCRfP5amAFxNpnrFU3pUykVmH.y4SUx.jpWGGJM9xaPkdN7ftnWmt7SU4iw6vYggVnqRurVVcbwoMvpmLDDxIUbU3lUB7FPBrlEwDE5IypfMCzoegh11ZSepIXl2WX_rWWTOLZSlHI9L1eLwH4gtmlHgoqYBXHuv0OFOWjxVUvFCVkF84RLSwPSAjVUkqIKPTVsXZ6Z2Q1K2LP23UpcZshKWXQMGen7hR.FOwoYc.laLjjevEVlNPx77egtIZNGjDpTfoQktPV9uXl0389qP8y9qpdmE.bOp7.lx4O91TfhlHVrknDbWu4vEGYujKsLarTSkx6DVrqsGmKq6ZYiF0cU2cpOpZknx9Upvw.pOCYVHBYuR14FUtqNA204mF0yvLgtCqONNxWDc41pFiZNxlvrabPaqMZ.ZtvtH_ge6OnAWTDH94VFt5k5CVlEYv6NLSzm3ThPzAlsoIFY5wZk6J75ffmrnTR8ZQlOjTNDKvGN70r4jbor7JQTiNrh9dw2cPCIFK68KaUWFfqvmcFpurfZAHuRtpYF3GxL7kCobwJDyxWPhMRqTFaDslggTgayKQedWeQvGffey0tz3sQRVejwY0b2yXb92G5q257shg9oSdDXZ2Ps5q0rLrbBP23Bt_I4ykVcsULGX56tmolEb5DwVRdpBeNxrHlTsnrJvmut3GI88y.ou5mz58Qr.al2GXhiHn5Otzy218t9wILtcZ2JzqLK_1h4kr7sJHcfJHrSdF3cRN3DyStC8spsnnV.sr6AziCssn1olcs4gU0PVhUCb6VnKxCeq411WenTchgsJ6nzm0dPfaIGQCxVlVvs6rwjy2FvTU_dICH3rkHMaP1OKz9p.GrlWPrQQBusW5eRKfXrc9PebaO4lJQWLPccN_hrtz7lfGDPRj_SjFD_60LaTB6.4kvaOEzP0BnR0BkjaZzi.OASNpkSow4ObAlL8Gz_myBPzjbatl69ukdV75fD1636Gr62bvLioWCg7EBdvl.ADHd3g3yvEIy5fBsKYE4dBLoZVYtywg8uuebkVdN24oYUDwMwhFzhB_DBAa8WZCzg8HKBZuzTQlionM8dV5qmpAEhr7k__QXiPGaA0YgVjim3sIrn80yh0X0rztTRmXOMcpjmv7yAUpgf1Bqlu5dUIu_4xuNbVXvqlC3tHhtKi0LO33WOk36qMfTqInklgMG26wCB_qmNwJ_n.TJ253j7WCsIQVWLQsiiIFuPjWNNbdsrnDJl0p30ODWkWtOCfM3IQ.gKb7"};var cpo = document.createElement('script');cpo.src = '/cdn-cgi/challenge-platform/h/b/orchestrate/chl_page/v1?ray=92dd98eec92e6015';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, "\/1291.45001?__cf_chl_rt_tk=4WbU.eTBoFdiYtJcuXz87rHwaUX0f6EFruElW7JPJZ4-1744239382-1.0.1.1-tFYy1vhc1PKmyq4q_DWe.llAalqOQmvbg1RmgROuXPY" + window._cf_chl_opt.cOgUHash);cpo.onload = function() {history.replaceState(null, null, ogU);}}document.getElementsByTagName('head')[0].appendChild(cpo);}());</script></body></html>