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: '92db69223a325f8d',cH: '1FF0nwxMHvD1Oe9dqK0.yKDH4MW86W0EubfzZPrxqnU-1744216453-1.2.1.1-zLL0ogAo5xDyKjV_X42flavMTzgOH59jXt9YeIc2JgbaLgHSiof50GM_QxQetJFD',cUPMDTk: "\/?q=rf%3A6948858&__cf_chl_tk=9tZkJIlIOsaRSU4FOIcfKPtOkV9v0fKcv5fbsu0OG9o-1744216453-1.0.1.1-ZuBFXSh5ZcJY1qUKMus15JbOhU7OQE2GS8Yn38Yb95E",cFPWv: 'g',cITimeS: '1744216453',cTTimeMs: '1000',cMTimeMs: '390000',cTplC: 0,cTplV: 5,cTplB: 'cf',cK: "unsupported_browser_beacon",fa: "\/?q=rf%3A6948858&__cf_chl_f_tk=9tZkJIlIOsaRSU4FOIcfKPtOkV9v0fKcv5fbsu0OG9o-1744216453-1.0.1.1-ZuBFXSh5ZcJY1qUKMus15JbOhU7OQE2GS8Yn38Yb95E",md: "G42omte5CeVYxdlJ4GGQYFoDYaSChfNdN1fSwdYDzyo-1744216453-1.2.1.1-98nsYfgAcWvffD2HdP7COIVIRIb3mY4H_qAiE4aION6UNLCGWgh3hV91MWEgwAsJ8wldjB2cis8lNneCG.LrWurWTvxpRjeoKEFAOIg6wgi1d1.RDjuVGGbHqTExowYXykRZ8TefR8hTJ8d.enar48BXgKhRzT6tnGsmJyOvQ1fHfPJMwGSsGWwThhfEtgjLTlxHGy0xz3ticuiXXt6ZVsImDQ4bcYljaX61b1NT8jY3QwEUdIkjh3yOHcQhjSTQEev4B4bt1DsWsHM.2_JmG4SkP2KHDscgrS.WmtG0L00HpJtGJnhhrmpS.tf2SkH2FXduFaVVH4nsfEnaqmhvQe6CYc_ZLN1Bs3jeaS3mtFSjz40LxPZUE97Dn34yImXob.USIcfPtE.cpqP5wcYGhyJ1zic4AirLUj3UWd7zaGd53nZ1ESJ7tt3kfchAsJJPFM48mMWZe8vp.FZk2F9wZr87eJXdE2wnPDOQXVnxfuMQ4Fgez0qPUnmslQABQFttR7QP.5MWrNZll4g5KyWjAd5wJJXSnnzwRknKE77lEdALAAxuN_oa3Goz24F7Il4KqJV1xTsQlm_1aLwQ557CvLjaUOrIp9.BCs.WFsVmpSwAD.PlMfSf8b47OF5uCJ2Xhqq8p6K9i2f5fB4RVEWdJQmyp4Ng3WjthlWNS2PTWJs6_9e16d4ekCgbQnrS14.rab.2Mmr_pltu_TaeX_vY4z8WYjbZ6irqQxWokcGrwtQwc8Ql05Fp9EwtpM9fltCU6tNmysmKCplcPAvpl9XsM9pEzWvFyqPmAOatyPWI6P_z79Uq4R9pMg9BoTx0QOPiKkkDxlVZFUxuYmHN9J8y0XvbIcG1urSPHGNGZnrL32wuubyAHmUNTA7XeVbT1fEuUPO_2orY.6ZJT_5eUs0Oluo1mphr0_tjPMek0rcpDlfbu3fFEaR5t.xFstuQHJVjoZB9QMoXAZ4ZukR9iZyL2sDZRISoy.Al5V5nsOtXzdx5h_rF_gTbZB.0EqBu3XS4oUDb9DcATuVaUYfqjtaO4gtnDpABQejd1CK379FhaVHIvfW9LVR5ZrmQ9snqx6BsdiM_gnFzbhoQXIpTyWKCw9RZZLerW64TBIB3ow0qKVUL47LgPSgo17ZBhbp0yBDpQjGB1blkjpxg5OjsPgxE9qQDKaMpEgalYXEyiTEO0x32_t5W7BbkBr6JnfCrk0Ac",mdrd: "OgaqnZ0FyqqkMf.JJb31ixmtjm2SpjyTo1rzbFJ9mC4-1744216453-1.2.1.1-q.5yWKvHX1fchwR5TWY8U4jGuF_5PYUNNI6VKeYhBEW9AluZxJyo8jvUXQdYvGD10KmlnjygSDX0vxob85.UpVPgXg3APDx3SI81gXAgYzCqy1jhE.z90cgvZRnJDvjrllXvteHKDr22KMKcE0.98220wLShEAU52y_RlfSgGpTBeIbwLSHOxBvSda4urPMJZ..jA6WoCP_G2D11wAcBc77wp88MdXsEGdsQqumUYQ1G9QLaM_8_I0EBLuYzmymP.J0jLULfZfMJKqUd2WyJWuPm.NDH8coGqjIqaxw457OI5kln.wLZucvkeDZXgn4L3JulkY0U2M0o8kA2cGP9DHKWJ7EbU0WgKSb0a2fd2LIclQ45ZS.nMP8VKDUmIPyQBVPrJ.XCP0b4xKiCN_CZt5H61qGnQfxlgrXVXsn2PaLHqWRoq6uIL5bLoOezViBYBT4by47iVxb9H4SAz8yr9GcAmTx32TlRVtE9iB2fHne2XFoSFjdFYVGr53.b56xgGU94YOPk3Wsk0CwHsxQHdStKt3Mayalwuyw0tlvZFBS3ffeFpLpFTknV.4jhMD5hSrwq2m6AtWVYWf8cTFVrgYnhxwpFHRMKB5XI07gidZdv7kIsOx3ZFSxhqRB0Hf0yyjNlpQcusqvS5telKQccKPJ4jzb.ijTFzsK_2Otln0RQK45491aHOghTY6hNXqWaxq0tJ58WerMNDtJ3YatQ2jrGjza9p1daa8ADjaDZtQjtX6xFZgfsizcW7vH3TgTdmXT6i.43gMNJljCHnmH1vitcrbB9KtghzW2PiDDzvLOgkQQalBxHi8omh9NV1UvXBaAShkECzG2Ag4SWwMj_9J9Xcbi.ShLPEMzqV31k9IStBR.wpNZDxqPjnch6IYkDfM8RGT7yqR.rec1AZ5pUREnkB104BUKPHClkZu8xwV0T7sEnbCcwoQmaCx.Ordph96eIcQ_4nkBdev4yMkwfSme5hXDGAB.54Ui7YsWAyl37FCPds__Zt51YeTMilBRtjgT1TLqulGyi1e8Xu9lB_T5tupYW3h1CtAnjhw7P3WcV17PlwwC3Yc.fNBqUeCGwgi0LpHZkTYAxSuKIqRz8wq2XNGt1PG0LUitwoV1pDzQQAXtn6HitHnBE30SXW6X1OpdKze45s0hNBh8XPVsL15njJTZvmN3hX10p9Jg8_D4gZMgv_OVa8AM7zDz8LAlYVk88sZJ4RHTH3ZUBGgXPxpBIhb1nvk5sPeQN4TMfHuu.jv1IP9C9V7.BUmUUPjaHD3SajK0B_V5aOJlkqYLdGfi8QY.MY1AEmouVU.JRTACSwwLqSRRrshZ0gPIh1nQRzXzBjBIVd7XEAimIZDN.LeivafusBXKwNx0FbJ9tFTjh79Q29ei87wwpGwFHwWXk8LG2EO3_ZWMV3gg9zku14ovatXe8hSkmmqlxxxR0OJLCDUSopETnqt5tyuODczWDfwA8WjEwv49BDm.ShDj3.v.KAdgyV2X9s2kxczQo99u.oVccsQbj.8qHSF.zVyfdweIT5g4D4ioMh..YsAhpHyr8U_EJuiPxKEp1rH0FFY89GqlDvugc2DE8DbsAC5jmbS4IjyL5sU4R4uUFX_oBl6WpWPwbKB5TbmjB3DnTHryUFK8N7Fe4lzcKxNNi5oi4LmtGpLqCaa3WE4TNPpUZmpwcfNkz55fbhcsqyD7AKyupgj7MNg_4iDwBtbC5eu9qpJat6KAs.n0IosLevtZy8JRcvie4sI7jdsEhbQxYcFxnmqTqHFfUne_b6XHOqtInGEhvZs4HvuDKykTQ4tMfESpPEzAIqs155mNjKmRFwhrHQn5Qfn5m7oO6PQYijCo.lAKyq4jWnknC55nssmvMfNB4iC1NNM2Lg4rBTMPrP7m3CnYhO1sek9hOVUd8XKTXs8tzNDVexzI2DinlvBQYwCmGvQOzO7VhvuDT8Kjwza4q0BXJQ51D3neqcFNMc6ROK.QGfu_CyeoKiCcK8lpSoq12XcyehXJtXSDPGc.UGHoW0U24Cnz21KgOGaTcbLSG"};var cpo = document.createElement('script');cpo.src = '/cdn-cgi/challenge-platform/h/g/orchestrate/chl_page/v1?ray=92db69223a325f8d';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=rf%3A6948858&__cf_chl_rt_tk=9tZkJIlIOsaRSU4FOIcfKPtOkV9v0fKcv5fbsu0OG9o-1744216453-1.0.1.1-ZuBFXSh5ZcJY1qUKMus15JbOhU7OQE2GS8Yn38Yb95E" + window._cf_chl_opt.cOgUHash);cpo.onload = function() {history.replaceState(null, null, ogU);}}document.getElementsByTagName('head')[0].appendChild(cpo);}());</script></body></html>