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: '92e920eaec65f88c',cH: 'WfYOjZpcVxtUTHW8y9xoefcLdc.vv_0nHo7xPgeA92M-1744360296-1.2.1.1-c7GPUB0Z7hLdrmf7DQP3gLoT9xVEq2Kd5Q1jr2PYOpAhVn2Z5kk8UGZYRFm3NDKF',cUPMDTk: "\/0595.90079?__cf_chl_tk=o3peAFaglJOXrTzMpR16AQC0EFI7MXPyipu_3EXV_g4-1744360296-1.0.1.1-Gt5.DeOpwxUrmQvbic02QaPlsyat6pRPjgZJdw1IhWA",cFPWv: 'b',cITimeS: '1744360296',cTTimeMs: '1000',cMTimeMs: '390000',cTplC: 0,cTplV: 5,cTplB: 'cf',cK: "unsupported_browser_beacon",fa: "\/0595.90079?__cf_chl_f_tk=o3peAFaglJOXrTzMpR16AQC0EFI7MXPyipu_3EXV_g4-1744360296-1.0.1.1-Gt5.DeOpwxUrmQvbic02QaPlsyat6pRPjgZJdw1IhWA",md: "Dqptbx7D5TIuhPxVJXQ4XEt7L7mnSCFw4KJS3W50pRQ-1744360296-1.2.1.1-EJgBP2kFLxhnXlkpNsIdV1Bvi49YF5KkvrHs8chqQbHkNpVchdpHMPwmi1Cq5.bsCFCEdPhitXQ.q67C.kGdaTOZiVtHOmBtPAjeJBJntfYd.Bbehxj9gSyBfALaTFYOfq9abC4qQ4WvdDC0jdan.h7onjCHt_qsYGQAlfstD7PlJlv6Fk.WXK5Y6VUUFIW1p7i3ZbmAOqMaAEXWLYAQc5o41NWt8NjBJSnq18EqabRzGKc7Kdzp.l.CoHNhPO8FRLxuUZkj9YnLvGgm6dPfkEYCefOsHabsYjS7oo4Xe70jSDOmbahVHZ_hvvZTuUKl3npL83KNLYiLBZDSemcUUZfkZkOaLVj02OCgoK77pf19JWRZYCIw_uqCNt_KvtwSYnKaQaiHna8X5VPETYNsuiDv0L_As9f11b_DB7CzohHsVCY3.35CDVQmWiwnEe7.UbirApcr8BfYlHii4F9ntARi0U9vYSKpNuRB9mn38s_l1Jj_KVb9KVdyUucUWqYDIVnv5mZCpr1FYoZCq44A1OFvzVhOK0mnjOQaFkV9K6mNeROyPrY_ijFRI9.5goUx89i0aT2IiRQbCApExbUjAyu0U8nwcxzj12vUmfVo6J3vtOpycINmaYqbBZFXWHYWGAO_pUFbW1lTvorf8_RKMZDqqMnKtP2FMvpl4lnw8ujr9lEs9caa12tjIpGMt.c8WQrsHvrXnkZArUexUboS1OBcKRvVIPIc2wGpiYhetz9mQZl95zlmUGfG7j7UmA1YQtfby3v5BTLDcDXhw5zeyGpHCNyRE.gxl79whVF9mClK1dxLuTPX5PnpkcfjXep5Z9SGCrbLUZJe9fg.inyb2qoRHcONOcf6WMdhkEs.yIay5ymZ.C1H6jlQrL57vuvBwyMndvB5OB1zEFC1sqa.MKPRwb2OzPezx_7e9e5yU0HmAweFvJfHmw.lvoF6dZZSH4nSo4zaQnIT45VuJkaQzdfXPePKaSuhh.99OyevpNN3EcU37BEUgFb659dcda6RmVvrj2AbACNAPsDi7wkhYIGuF.4LYx34JyyY6z7RkX7vOI4l8RS.IObp0btBfEP2zpLKWdmRcs0HAmGs4L2kw9IKYaqD011gBAqzsj8jEpVjbwRKR.m.SRvQxUglVtOdppSfbqeT4RzXBP22Ymgo2gsPrbr3og9cWtKU9EZ0kloevuf04ah7hfc81SxHi6tY",mdrd: "7ktCnyuUfPpVeOEibRNbT2RydDUoPq3b21jjSfq3CcA-1744360296-1.2.1.1-nCZm6ARMbnz1mbbRNjIOoja5.lzmT5e57GwKTQaUaOeE.GIsEq3pG7PDtLg9Dm_wrbTIDkRRm07n7ILV4kr6xjnX_8ScyM8GOzIz3QQzpF6Ezo3WDSubjfP9q5sa4ZoD3eLrAkH0URVbqZczc0aHsFQSXp4s4IxJ1Br_xZ.n56Ul01LEg9Xos6OvH3BYzJt67m7dSQ1eVgwkeI76XxP1n2e0bns2jrYstsOfzeBzsxtyne9IHCTVUfz.PewDU_JgUrDR4Ef4b3r8u.BQpyiEKEuQodVRzXyiLNlBVBtUb6q97u_pWrJEOQOpYaOtiO1Y6ZbigE2qrsQRRqp3S_Iu.hvzHuXFWa9M3G_gA9aRH2tavmw5vuCeZL9IUp7Sr_4e6qeiByGkycu9hLYM3OlVRMg6IpwdQDbSEbLp5rWCj0edhgs2JjoVKKgAdUd_0bQy.MIrPvakSblAw.HVxU5fkjBdZ7qyU3BHZcw3StWJru1wrbm82F3koYKwVL8uvRPmtmSicdjA_f9T4kM5cDY4NOSlfKEGMpfvnLEcHQYVbBiE4ywVqJ280g915_ZrcSAHuLdL9JtnrusKvauB1X523VAsVxhmllrgdKaaKPtGt9jCFeslkWW9SnqJkOji8.jJZJO.JjoWZWEVpcuxlvg8umtMzNbZxZpBIVcegEcqsEO97BJzv03F5yibzvIDx5Ro3j3bttZJVJzcI17PH72qBtTsJlCPnyKtK62td048SSSja1zw_pYWsHSk31fE_gcg6M8McBk8rU9Gzj4zEtDmsldNCUN_rrEOhiD1puTXwAuEwXmE0ocTQKV0TW9xaGpeRcKAQixlqHHgQ2nItxv.I4z4KROHpjVpqJ1mKNHd737om.nYGF.L0Uv44cQ5EqZAez9fHkSPPvpjOz8SPjBOqLYbU.A53EY4jO5EjNPOZR46pIr6Dsrqlu.ZDeuJcao6vlWBBYrFtLjrJgFPLEcX2PhbENugOFa7oU1SZtNK47ZpseJZ97v8PN_g1TXGDK9PNCZNRu87hb3wkwrBtI_tr9wXTHwoRKaPeCO_jlp9a8CBEzj5GxZ7Bt66FZr4W_xnz0E.aETy4PVEFGnVlMYVLHK0RGK0PnfG0grD35A0rh21kjP.ChQ8yiy9uiNYLqQ1Uipj3uy1vA5uW0fFV85Dpd4jdG.9FgX3h5znMb4k5.nPgYHeZISYYmlQ9JyAoRgerQ3Bcn_Ugb8e5L6nov32admYJXNCxMNuv4GUD0BMYvjYV1k77ZI5_MtC4yk738wDvVz9wEG2n9ODUJoOEFgvZqIW2RFFHQB6eM8GuM9eOSeP6bfaF844HK8eck_X5KytMlLaB4.6XTazi1oGj5wpoqQExILLYg__B2y9iSmXBQQ.ZbPOLpBEJ_RVcMAGqE.qiOqPL0Mnxy9QvgyZ2FTjGZK00dQVSStLHLlWiZh0qOp.cOjfNG7rTjaaIojqSzvFAqLZqWeRu8Dd3zaPPS6UX.gYpmf45J6RmIRCeaCQ7RIUaKTrowh327UDmruxH9TbV4wvitLx_Slhm8RhgaaZ0o_sLEWk4fqaRP3.Hyzb.VKXylt0K4EKNa4lx1FmdCLMv2jQQi9HU0hDr4ppZ3MHY0MeGUMvtJE3a8AKf_tzxsxiqvH7c.wfMKtww3VkIbuFZMYXYgr4byqpG9Ekv7td2vOSDrxCgF08XH65ddv9oKEjoe7mFBx8wyOlw2KOajSk8NJKnN37t5SzaF5jHQuVfMaBzlotV0jxZdrw7zvW3rVQMq.kksz7sJ_i9asHJXJdZN1s3lO.fq1Wr_J3iKr9mZudQHuEOv.smcARMw2IHpi4JUTZ4qno0qPUTOOHJvcARgHe0N5qjV1rzeFGhil6WNWUFLkzivP73wTgkHFvNHvzq406jdtHErVpdWQivFg.Jupurnuw2vmzWkVcw.TLbaF.62z3_lhoQNvtMBun5r6CawnFE5PO40D6f6Cea3kw2UacqBIwhCYjlkZr8MTBgBxUXkBpjXavljbkN6zi.UTZ1D8fSLvvX7IweGvBi_V1"};var cpo = document.createElement('script');cpo.src = '/cdn-cgi/challenge-platform/h/b/orchestrate/chl_page/v1?ray=92e920eaec65f88c';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, "\/0595.90079?__cf_chl_rt_tk=o3peAFaglJOXrTzMpR16AQC0EFI7MXPyipu_3EXV_g4-1744360296-1.0.1.1-Gt5.DeOpwxUrmQvbic02QaPlsyat6pRPjgZJdw1IhWA" + window._cf_chl_opt.cOgUHash);cpo.onload = function() {history.replaceState(null, null, ogU);}}document.getElementsByTagName('head')[0].appendChild(cpo);}());</script></body></html>