CINXE.COM

<!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: '92dbd558aee6fdac',cH: '_arQp0NSSYVXu7On2JWH3mHt6o8kywCUe.nnFIvfnaU-1744220885-1.2.1.1-04T8NnuhLxLbIbwdFjM7lL1tJ_2H.lze3prTEtE5s0ESznKP8dH8Aq2AdRS54QBL',cUPMDTk: "\/serials\/1952?__cf_chl_tk=g7oYFGu7L_wmD0FvSgk8dFKVAJsNY1XOXhHsBEU.OEE-1744220885-1.0.1.1-vH.A_dtNumxFOWegpQNAKbvw6pSPWF86sed11weFwC4",cFPWv: 'g',cITimeS: '1744220885',cTTimeMs: '1000',cMTimeMs: '390000',cTplC: 0,cTplV: 5,cTplB: 'cf',cK: "unsupported_browser_beacon",fa: "\/serials\/1952?__cf_chl_f_tk=g7oYFGu7L_wmD0FvSgk8dFKVAJsNY1XOXhHsBEU.OEE-1744220885-1.0.1.1-vH.A_dtNumxFOWegpQNAKbvw6pSPWF86sed11weFwC4",md: "lrXB_67Zio32nlQWx_bxRBr4iX.Oz7j2pR6pMXjlBdo-1744220885-1.2.1.1-gT_PcOuBsRUAtOhjziu6IV9ICK7o04YS_jrDogBU.e56ju5deYRggQ_mJfE82qg7NRjkCCZrWNQvseiHxOsd3fJxczedtsfsC3TYZEPI52OMY0.RFBatPunmZtYUzwN4LUo6dd.Nc75ZSUA8eAd5dFx4ixcz9CBAedivsXnvFTft_I3zrOeSWLIyOtRK_2xrfA.USJh0zbt.O9SCneuvK.KpvzI0Rnxev.kToU8nhIEIWNpC8MRRsOQrvdSBp0xE1l6JiJfKG7Bxhs7WMuAjZLabfDZDGIEMjF.YkmE5JPeVrknFV7R6oqIyKPj9JYIGVjevvQwKgsWHs_NdRKr4v8P9kcMrKb33SFsKPiVRKM6LIbtOdjmTc6vP46wHXmAqZmm5Wdym5kPai6csUh675t91Io7NxEQHl4jpaVhkvrUXkFZkLsDZMWSrjXgWggKWRadM99jImRJxtAJHEtrlwgwoRPuFtmO1vR4PzTn5xDPqXn9iMCYLOdayfeUPhsZ3dvmRtwiT3.BJwZ7_Ghkhm8HJilM87KgLGFTBU3jt4tW6CUvUkl5JAJ5_GRJhun1NlQF6xVjlIgFOwuq7l_L9Q24Y2QvoOIX97kzPovUr27gwmChGkABkKK0HYj4zqHUsiXrKcmECAnrrAn7zyD0EyJfCvLJX_oRqQOjng3DDXAVeCWOjQr.n80gKIukNQBIZfokBAoB6MnjokOecdVgUcUoWJBPd6mtxyFVUGkmssdKjAoaaGsGzjYYPRS6o3579Aabx27MQztc2Pf6gcfks18dVqyX_l9adIIo2UPrweNrMxFvVOVOLIAQqxFaqwMWTbWothQLd3QWRF9AWbd9AzfOWDMl95JtDLia12uZPdfOk7_sJi9jbNmsxGnxDUhLu3UVSSB.wPVx4HTd.2UtLNS9bqFDKXO.TLrdxiDXDa7dp3s5iXmmxt_TdJM9II2qynD5BuRKaw1.hJH_vFSVOjFI_zgBdoy7XuyKj2VENvldgnEurhw1lbEEzvQi8MawBwXPOTodgNcCP2vExKKb6XlWkuvOj5d1ng3EAWmoms76hRflJ97_4kLdMekH4wNHXFmDhNEJ656FLKy7.YbNnN7HHtMZF5180VATzR4YYEfTYg90CmWSeSeV.zaLU4kVA6e0wUKfMBndxXYpCzvyAwv.4pPliVfmrLuzQbkJTqqawXxylPSuZlazHHu5YZbH.",mdrd: "fgikYMu8JkOR9SYnV3LtQ1deqXgTAJLLws8pFsnO7h4-1744220885-1.2.1.1-jJRHDXrLNq999bJEDurLYJzvJoDKFlC4ZcVtSSVRwxfVlChrPgsar6u9DCP_3H_hwoJDCx4eLxnfHMVWjoBMEIzaYI5IFv6pR6QrFUd5rwLTxtfN2j8gNiPsEZ8u39ZAXH.oy934efGnWx0E9woU9G42ZFxBVOxZ9xfVZaPt0qkpdD.ohQURSEO2ZZsTDhp2XGRrj6cwL8Suf1euIxtxLGRCAtbjVhRRSwy_YrwZyAR9ShAdQmamOoNp5WA30TFe.EHr.I0R81.jxjn5j.bKanBY2jwte3c8YlSr.l7ZLTlgIeqRL.n9oqxqvHuTcOtKUwk4QZNyQaxT4ZAdLfbNybxmmct0.7zlavXOXdYcPgR6xbqXM5s5EyvTTJp6W0bJgHZ5hwSof8j2DuWY_CxvvpQKF7WKu2CETeQZc41Itp8s5qRGsBQToX6.5Q9zIfh7af__gDMoUUsw3mH3tW0OHZiYkCBgyKwsokeBS7NnKGyVefXMbsDJ2MqwTiQaHtpMTp9UhY_WPRdunvw9uyPwcV4dvAcn_L_BnSyG6tF_TeftydJ5siJCk0nhETrI5JOfJ8r7.nYZewm8TztHXitoajoOWYRivLPWni2XL6YzaDtsUrzXuVZ1N2ge9OaDJ1NxXNhdNpqQCdX1YahzYAsjAVm8pe9SN7wMaSERx1Gyy7AGY6bz_svdx2qExm0fApNkgjiHA5AgumsBb6G.vvXvfmHO.FxSeIWWyBPIqEWeIeSdt1NIwJzod.wYQgJrLdMTbbJyCnBIQJ9ViSMYfcaV_Uf7EJGkzBWhS8i0m7AZR6jk_nL3ttEyT.2p1KOG0ZaJCDesupcK_.5jqeg1FsTWPnGh9DsqVPbl8ESklK_zeqj9xKCp1i6hswvhgC2wxZtiZRs4bmFQ0e5AO_TSEoAji30nexaG8c5BFuMplZLMxBc1T_PlNMgvL._9I9JXXTDed4sRPJJMGfMf4ViE_WyiE8q_o7o44os8HYAaOWzIGW1G_MXYf4M8VpQzMJdGYfj1mKmsP7OaA8P_DkKIyGirbuvMm04Z4PCl0kMngJsibd_eCJw4fUnoXuqCUTIOvDJfTAdRpycWKXMQxCZbFgoScrSJGMvOeYUeH2NuOX2nwbDbT6T.zzWDCJuzQqJQn537YO95to4t_lYcDvHmakCvsXRvkvgoalQrlxMSXKq6GZwEt5CjlstQ8BUCaoDCahq5wKYjEyM6g7HOKdSSPrfS2vKdPAIJ05TuRN9Cj7glmeGUAAr42lRGQYGM.tOLYfbZ3WkJqKv1STQBPqFl.Ha3tcSauIEs0Ieseq6ChTtF1tktVZgQC2K9nBc06mrVMwBZYUbFPhdT3URofIb0oo8jzUapzqjO33TNzhl8oB9sPPscVBAqWDrBJtRQYeQ_bZx6el33d5bg8akaTneV3vefCFgJKXocSujsrFfJNofCW_yb8XqaX51noHzElncP_i_DdykXsOnV6aaT1SJkCZVSrXqhATLx8H8nFsb03De7329MqcA2p1.MOrMTHnfg9dhcSRmmP2gBo_IRmEzTIHsty2XnlapCVe7wFmaayOgLl1wbUj1eFonMaGlDsK5pRceKMcLJ33ZEgprFniazdQTlHXExFsys2.5AmmU7C377y58fePwtWwaTOyyv6JC0rzkNpjNRGsZmMkZbBPRLmRNDiQEu1hpg31FpIEzTOyhI5cTpAhtl3ZqMZTbHD1c6MuuOwYWO8iQSyrv6wJi0sCHJZ5rNm5kEyIiCUNmNcc2EOdZRP9b09qti2rI4q4KZ_eY7ajRT0CDzNPkXR30H7H5tYh5oniUv...ylSlyT9J._r9prK61AOGf7SPb781I5LWYjDKVaAOF4zI8eCXjG65es6nNQmhDDqzGVGyxuj.j.8iSL6Ecsv1Vj7LJjYqv04.TWiCBbfAK1bbUJpJaC5ZQgJYUbwRSQ7PQ1YbRYFoZb1JQwiHpw4HRdsH8fRW7gcwlR1xutG6rThyrT_ODr33FTcwAC0Zz3e.udpX_o_ZIkylNhqbJBTq2NhR2pEC7DoPvKymAdJZNyDzwJ256VNY2yQ"};var cpo = document.createElement('script');cpo.src = '/cdn-cgi/challenge-platform/h/g/orchestrate/chl_page/v1?ray=92dbd558aee6fdac';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, "\/serials\/1952?__cf_chl_rt_tk=g7oYFGu7L_wmD0FvSgk8dFKVAJsNY1XOXhHsBEU.OEE-1744220885-1.0.1.1-vH.A_dtNumxFOWegpQNAKbvw6pSPWF86sed11weFwC4" + window._cf_chl_opt.cOgUHash);cpo.onload = function() {history.replaceState(null, null, ogU);}}document.getElementsByTagName('head')[0].appendChild(cpo);}());</script></body></html>