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,PHN2ZyB4bWxucz0iaHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmciIHdpZHRoPSIzMiIgaGVpZ2h0PSIzMiIgZmlsbD0ibm9uZSI+PHBhdGggZmlsbD0iI0IyMEYwMyIgZD0iTTE2IDNhMTMgMTMgMCAxIDAgMTMgMTNBMTMuMDE1IDEzLjAxNSAwIDAgMCAxNiAzbTAgMjRhMTEgMTEgMCAxIDEgMTEtMTEgMTEuMDEgMTEuMDEgMCAwIDEtMTEgMTEiLz48cGF0aCBmaWxsPSIjQjIwRjAzIiBkPSJNMTcuMDM4IDE4LjYxNUgxNC44N0wxNC41NjMgOS41aDIuNzgzem0tMS4wODQgMS40MjdxLjY2IDAgMS4wNTcuMzg4LjQwNy4zODkuNDA3Ljk5NCAwIC41OTYtLjQwNy45ODQtLjM5Ny4zOS0xLjA1Ny4zODktLjY1IDAtMS4wNTYtLjM4OS0uMzk4LS4zODktLjM5OC0uOTg0IDAtLjU5Ny4zOTgtLjk4NS40MDYtLjM5NyAxLjA1Ni0uMzk3Ii8+PC9zdmc+);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: '92da60f059c29d12',cH: 'AUEkh2aP8sJC8lniJE9vcj9YM7BBWEmEJvGewDw93vs-1744205632-1.2.1.1-Fg8lPXFPFDvAt.ptugKafruR.HVbQO_sLQoOM1wW8GWaLUYpl_IhahCzd9vKQVqd',cUPMDTk: "\/0501.68053?__cf_chl_tk=14Ka.PfcqjCimfsskGqXFQw_4Rrx4I88la9y4tIwvSY-1744205632-1.0.1.1-eErW1yjxsr3fgKOPiZX3R6KrBSQGVOp_fTKQvhkukYo",cFPWv: 'g',cITimeS: '1744205632',cTTimeMs: '1000',cMTimeMs: '390000',cTplC: 0,cTplV: 5,cTplB: 'cf',cK: "unsupported_browser_beacon",fa: "\/0501.68053?__cf_chl_f_tk=14Ka.PfcqjCimfsskGqXFQw_4Rrx4I88la9y4tIwvSY-1744205632-1.0.1.1-eErW1yjxsr3fgKOPiZX3R6KrBSQGVOp_fTKQvhkukYo",md: "l0Btk89hgLqU5AzQ0cNZP3gUyN_.AUjCiHLa2aq.ZHE-1744205632-1.2.1.1-AqnV6wZU.fGskBQnvdp36Ih6.UfIHRV_FcPVx9exLXCmMpam9VfGqCIc.uXpH_LzSyBcxqUL33Ah2BCdKpx3gv9i9Jl68ec7xaVHYrCXLAQvXmVDmv0NSahJxie_VV3oUrmdQK0s7N17IjfXdXVSpzVEpuBWpc9aYTf26QFpEse.pG1KVx2_lUPui8In420k.3MoP16wC0gT43WX.OGmWK5xp7xeIQR.cmYpqU3Kfc.h2U_GN2Zoy.98DgicZjifJEOa_posQVgSYSb6DZv5GdTj8JACM.LMZ06exuH5E4Hh6WG3N6sx5EmUKwXIrNQ.vWP71hDuFPQYCujD5J9p8qSPvmGU_81LvVhTMp8JbvSQn1iFcJMd9OeY4TSRiJL.Dp1WS0z0sD4o5HX.XsN2rqP6XnsEt9k6.eLw1w56GedJrT_DYDUEA_9Ke6d6JbBpxNkjh6bBRd87rYPQA1Fn6CEqoTiNye9aQV.YLt7N4ac35_CC.H1NA6kCHSdUi7yUVMYqcJTJ04uoWp5aTJMEyfUcB9CWsy8nKOL0rfWuiuZ7IumuEOSJprroz7lEmZbFHofD_QnDeBsONDsVYFYEaUGLWcXEuqvvob9pmsp8khFFppWVIX.iPMeK8gymsGP2QBM7sifvuNd7sThttDoe5QiPj.aN6xxNjsH.QlnicaD3u4pks0ZI_LBBi97wxBp2QDyuIRh3B1rg4Y05VAD1AI0Yh50qC1T29_XzkC05BpF5LLG0zoMLy0rRWpZx_m5Dgwxjcf1PIa_rO90uMrSiLBzuNsyi7IBLhYKU_iLT.tqVgNqUd51pVMdKRswGEk9604cEupIyoab0IRYiF.QhKGdQHlkV7o4TvHdt4PfEHEGIgB5FDg6ewBkUvIcK_0sIdTS43Ksjthk6.WmN4oZKESL0MhQmH_BrgzbMc0CFkSDwB7oPE2MIBD21IQzdw1CHIPE1qEGNE_7_SXVQk4dos6fe7VgHivPUraqyy3eLMfl3xfX1plIqLISEtz9LtYCTMTfrs55_N_oXMX9pHTpW8mmhrLmEV_ph_FlB_k_8bLTW9ABoBTCIkpK6CYpJJ1Okov8jtmhx0xQHb3LJ0R_1BCwSO45sPSJC2DafGuZAcCtSlvkJspDyEBnve3R5m8ZUQHsI2erRWo9hw0NJmMt58na4NvekbkqtRTtWh7JJsIN142Gj_.5pUt39S0LZliME",mdrd: "n0TwDu.JxY1Ande8eigOXNTP6zMpGfXGDuk5Y.UnGhA-1744205632-1.2.1.1-T0Me28A.VJFo3TgEUBKbfjUquCwOcEnMDvlA_c0VMRqmvGo2QXNaA7T0Lp0UQjxr53wdOhUzMpKlakNIu7jm2M_zeiFROBqc5iALo794kTnxrT6T4J5yQP1hlL9QOTGp45WwH47tLrULHmnFlvbm.PCQ1sFQ4IKp5ChtTqD2SrSOcdhUUOtE5JiZqoVAo4MAnf9.sjMZv9Idl4WgZhr5EftDFJ4xHAE0wyGHXXoyjTBqcylVkVlc._OJym7aTgQLVxEM0vAD.U8k.hOPRlu5Slof87n_ELY.ZY9Des3Xkrz_lZ9UpUI4SK94zNhKkeomqL5Baa3_aQhaPYvo9pmjFj2Cl61BJKYqbzas61OKA2kV0UFJPfFv.qSrwUgyJjbpTTnIAc69F5RHd8y8Cgg.jU6BKPUioFsvqBEq8d0gUKNb2wkvNSaA84dJlwHn0SWKZJouZuQHW3I.kGrxGi_6TRodNzVL1v.DI5DTViEJeamR7wQw_jxyEymo4NE1cTBuR1JcHEmh50Ouf.yXq5M3J8qnwfzaqewkix8Sdgc7QPs4O_OdqtHoVgBZub8xX0ZirFLkyvhpQ9WLdQwnWXDAola2nFQDfdukujA1D2MFhIuA..XShroPZk9CPXxaZtRFiUiebvuOjNeG_TPmzfYQ60La6aWVZYg1_k362h6jCOEU0QtgkT49gahGvSs0kdK55nRfz62GG7Px14v_DzXYUT0jvc.m6Uio.9nBqzgHPzFkBJcdgEDw7hJZsDsOXLb5QIXWD.V65EyDXiuAJim0IsTBpDqqFSy06XheGh7FnCnM40rrrJPlz8lnntw8NsfmTtFH.GAZIgT1NhS8tv4dlHYrKo6Ul2966tl6EYTe_UOj4_fOFhE2Y8BJCqNbXZPzp9Ksm9zBPOceAe_p1gYaEpANyUs1S9WkL_3wW7KFHm9qdYT.7a9.7e77gIC5KqOZKU6hrvJAbqVYHTQ6c1n3I_6mlbJZZkL5wuRSwkUVoaC3SLkyJxUS.CqAhrqmxapLqcP_MtXeFGIGn_dgnSdMsWEVdjU_q8PDhNngXLqKXMkDkLWyCXIHDGAbCFUAPtEvuiLGL43B0FS9upH7D4ckmliS16JLSC9HjX5TSkeeIWQvs_0b6oE9d_CXvCAeC9zAWzZ9JR8rNLRou_onVLc1Of2tDbBuN1txlZFDcMV6_pd4wJf_El9aGwtdpgb_JqQY2fEQMzuqjZB3cuMZ3x3TxdgsTpOzF2GNr24y4qY0USJDF.VJtaIDPkfevNodFNSXfOHcCfqKRvAE6yo1aI7rCFHH5vkqjgEn5cJmS0apEhTEjuVtq_NWfqTllAckyAcctJGDf4hSuI0tGBcIGFDMJJt_RUxJzxFzF53R2Ebi0gccuxiLsHUbkYx3eISXqHyLfTmrJBA6ncYBbicnO6gM0yu1Z7tQzqW.WUKocwnM9x7lp9jRSDXT6xglPW52UDaPecK2ZylO8610Z9n0R_TTI1kjrcFrCgsp6oELL9RC9hmB7WxsTL7LjksxmsQZ88Ye0JFhnIWbn.9SDKBdXZiiE6.WmeytvpjHtcBE2KBai7yEAn7brjlRfYEyvdT7fG43NpDAavodPszstzTHT_MGzd9.3hPDnPNQPazlOJzVxsdpF.s9D5RE3JOrz4PZQm0VyqSikhma4DPwQmnPLoQdwN.bTHyq2Ibysp5jNgfdk7vs1LJpr9N9.y1U34PIsZZPZpFfNaSxe2AQBQeOKC_Y0FrSl4Cc3e469THraSj876sKcbNcitTpm1X5nw4PzZNS8aGY5Ss7RBtf.uw3wjbKdeNuVcH4lWW807GbGNo5lUWVoDRCHmA8sGyqhSmWPgx5jAoRJo0B.qiNYu8nqin6bDzn4sIGydcc8leSQZSD5Oxt.WvPN9G2QW5cLNrDTdrrwBBNquKnN3MOLTP7xzHqnmqi2ru2LYkfhc5nCgSVtPxhIKuxyIG2KhwcOh.pVsy1RTwhcysmX_lgUgR3QNQSFxbptuTlvYmNu0msduZAPvhinmuhPB_f4VET9jUf4vWsHgXmIIaCkLaoc8deqiJN0Q"};var cpo = document.createElement('script');cpo.src = '/cdn-cgi/challenge-platform/h/g/orchestrate/chl_page/v1?ray=92da60f059c29d12';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, "\/0501.68053?__cf_chl_rt_tk=14Ka.PfcqjCimfsskGqXFQw_4Rrx4I88la9y4tIwvSY-1744205632-1.0.1.1-eErW1yjxsr3fgKOPiZX3R6KrBSQGVOp_fTKQvhkukYo" + window._cf_chl_opt.cOgUHash);cpo.onload = function() {history.replaceState(null, null, ogU);}}document.getElementsByTagName('head')[0].appendChild(cpo);}());</script></body></html>