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: "oeis.org",cType: 'managed',cRay: '92d438533cf491c3',cH: 'ugZu0gs8l0IoTXhWku84xFAlFFjgqbdezIZjWyj8Xnw-1744141053-1.2.1.1-_w51ptjq4ooLW6.ZczsP6JbEI79nBkv83_KIHnGCKGwN5QIEQzHy.nf4B9YXhGMo',cUPMDTk: "\/A046841?__cf_chl_tk=Ihb3_w6RvOnuwFUF2dBExLuPdEIWwBanIJtk1RVcr9I-1744141053-1.0.1.1-YgJwzkPMvya3GAG.pVlzBXg81Oi..mHl3FHfWT1Ucac",cFPWv: 'g',cITimeS: '1744141053',cTTimeMs: '1000',cMTimeMs: '390000',cTplC: 0,cTplV: 5,cTplB: 'cf',cK: "unsupported_browser_beacon",fa: "\/A046841?__cf_chl_f_tk=Ihb3_w6RvOnuwFUF2dBExLuPdEIWwBanIJtk1RVcr9I-1744141053-1.0.1.1-YgJwzkPMvya3GAG.pVlzBXg81Oi..mHl3FHfWT1Ucac",md: "HXAMR3buvaXC0PPeARfKpUX9ANRQTyCSOSA_gn9MHeg-1744141053-1.2.1.1-0.D7EjnQPYXOMue9LH8la4hEYqATxD9GzwFkhdMsUl88Vdiic6zF8ffdKq3dDe.O1iIW6j.CXiluEzzfGP.JxKeA1V3IIadAkg3xMyDGMAtST449g8o3DCblgpx7vjg6gywtxWpGRJ9vOTGLc0a1zdZdUQujL7MXieIXyLiK1oZhY.TfeDJ8ztOEXcmHGSlvfaWSjYDJ8.UlOkRtsw1.dosSqFny2rC5DrLhxovXYNjw_MlFQ3OXUJefC0qS_19Ay19J2A7G.WZVVe2aEaVjlIk.nZQ29inxdNj1o6k4FtEhT8l.Q6jQyxhgvY8t7cPrKx__k0kKAK503XaToos5KRyHqDC9JkvPPsSBffaF2ZVFiyhezCZe3XusaKSelyiF9q9XuEwLbWv1INhQLeisic2x40dZ5s6R39pjAz7659rneIH5n1XUNtn2xz68Ve19791ZSj.iwldP8fim7iz48mu9ytOOjfngZSUnV7.kEeo3k5yHntAD1Huvl5qxsQmdwT6Cv_XHpViwGcO8G.u8Em6qf104mDgN7pbKSXqZwv.qrClt0n6nYUE6CJI5V5X97AEVTfu3Xup0OqznZFwlBVtNpHQDNeIHQAWQCRyxN9aIVSaJpPN1Mr_IVss1pLUV1Hgyepwl2el4SopyoRQLA4iwJi4nbj7DXPEQWknQNbt3DY8ZZqxORq_SSxS5cvM08KTiEwzO4ZpchL_736mX8R_U_OT.MT1wc8IUWHfLbVc8ktLErwuDOUh4NQKPHCxLGjGL6NLGG.vLBwPY4f7AVlUdfwHft4MMK3gJYqAGYjzMsFzyuYSXEnc75PCKE0Lf3Bl4Kb_Vzv.SCaDbPm.xyADpk5WMIdDMH9JwMpw.nHMmipODVy0ajyoOTQfFfF6OuxWlhEcRUlSedmpHxPx1hkj_AyCFZpMTEuf1CPpcmcx3URyAoV9TCyzYfZQUODa_fMN3WY_RmStWinRKa9P0c358w91cSeq9QQGHXNOoaf0Ixx78QXwe5IimHufuzC7bAXBOnJptLXlHNBNRFBAOBVhqhZjnkLfDA8OLmP9wzNgTb1NXW_f3ntAnjO3k7rLX",mdrd: "E76_OXbaFxWYFGfsIC8Mf2wHOFFdzsgJ48FrO4cE7yk-1744141053-1.2.1.1-0.e52Sbna3OP6LrvlgULeT39DKoTdnqcXmQGUMTo5rTzH5qaWedIX.kUE.yrZi8VfrsmTgus8eTwDCwwe8RYW1.2F3cfzUKsSQy6PkETi8oQaX536Zp7imtzVONrBLTc6d3cbBochNiJZKDzYTxsPb4BGzV__Wd2SrFsbb_TlE3MIsKYWjH6D1WikKpyPc9fBTZFbQFMfkDzEtVu2qgoIvk9MbM6pNg2KzAwImNxRnihOiq4t9KpcsU7MKA.qML._QfLh3QV5brEmBK.e0.R.ELc6wgu3zk73wErcvOX0D68TjAOCVmfMCwy3.HbDWiojOmFqAS7P5SLjxdhXocDExoxzBWrWlYEiPyuC04uaZWgBT1v0fWOsvkf3g2GB41nyZ0XwY8CUZDm5ai7WQoTlUK8yZmksImbUMx7LYOU8ZG1MLvZtR2tuzBYQ7fme_HKmFJ8VloT0G9bj7pHePNblAs6afJ_2OXJFJ68fEXOKs6ssLCqwrTzoXwOOhqVLRdhSwv8Z3qs9GRwO85DC9P6KeZXdkEalIWkgM6uDQK3M3eeKjmAUKYGTuQyvLADG2.6YFX7l1XAsqMSKK0_HRCkANRU8seIxWN.71NBFwu4fiYB7J1Avp6LSHcwFv1QQ7DwJ2pebxumHrxVIB6M8cjS14RepkxHhY5DkjLybj2aV6bZlcSHNj99Wf6NcDdsm4v0aPm7WkmIz_DFxM2bPob44EcGCE2aJb.yTGoQOVx7Alz..CMV3RKMpqxPFqPYoVQism0.qEKvLUYXZx9GH34GnmmgUpbubbPKr5nU2M3QLlcSD6M9NS.uFw2kK6YIwnu9Oj44ZuPNziQapODGEgEm7g4CqibY.ENSSuPZLyd4Tv93HXh6bu5EHsPhrztsyd0zfuoUmvH8hFVSdxeT3BqrbvO7vI3T1YSVmIEetr_J3g8fgbSOq1YwsWdeExO4.fOv2htcPDvujyF5204Zh3Gv_zCJsatUGXp1WGyS7gT8fR4WnRoeNfliYyz2QeRbOfKuKZhYripRg3vP7rMsNXKc_4qTZHC28NRWWCa72mkuStaQPDzdPs4gZ2HgyWjJ2Vx23DWZE8fernjlgxZb.n9C1cw7mcpNe923Yuzj_hJdfwRwJ8Uaw9B31uh9lMpKcpCtCkOjhghwvR20wW3Y.kYNk4X2eRDb.xJGWBjuIQ6auumiPOnScWCBA8VOc.bJxRc10qSIxbbj_OdzYP6JOmgKPwvuizV6Iv_oCLnZWIWVIc0dfDW76WUSBjI1NxOy4SAOTuk.Q1et.REk6nP7yr3cp_dHa3Vxy2QFqSVMHmSFqeTq5sAERtffm20P9kiianqIchEl9PIk5FCbHbWWuuMYcDQupoN2PgFZlmbZ0infD_vzLVcmBmgxnlIZuETdnTLCXMUbBx53fMVhFEOARMrRsUuNhZbhSrN6rofNnrxTxkdH.My1DsD.ZKbjnIhSjWmPbt5J_0gelQzi.wgXWcbCj7vDCY3Pa7OZj4qLVAxVyQPJNLRgBSywiiEF16LwbzsLjLse1flFbFwI4R9fqBH30BKYBDbf3tUlhEKjNddpiMBUCN457XsPafT_uS2urExP.aWX_u7kNZrE71PcSnW7cztNic7D.mo5pXBOmdE30oiPeZlWvNg3woHTxJEDpoR6LsYr.XJLOaiSQ3cshqf.O2.FscCY8VhFqupnHc3VRn05KZzIzOirBEtIe8IdRmiN9S10CKKHj6BZ1MewG77H04OjV3vu8JPdqtwxkM03IhM7g6H5ctQcd483gaL1rwF10CoIFC6Uc74.C8sobItH31DsUjot0MgVBoLOrlkQj_4OUJbCpeJlkZUIRycuPgXoNFFcC7qFYcHmjNvG4JU_XzKz5nUpCGFyPY6e2Q8uT6CtbgNpTF66auqoefrCnhEhLOyWCwfS5rq0.7z530tE7vNaqPaFsvknOzwADoyg9v5v7g_pqDZShWl6A9p2opOKiWeaA.npTEDfrpvXF1KNfreHhrR1Kajq.45zg9ApUv562JYHZDSzZt6kFWL8xODJ"};var cpo = document.createElement('script');cpo.src = '/cdn-cgi/challenge-platform/h/g/orchestrate/chl_page/v1?ray=92d438533cf491c3';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, "\/A046841?__cf_chl_rt_tk=Ihb3_w6RvOnuwFUF2dBExLuPdEIWwBanIJtk1RVcr9I-1744141053-1.0.1.1-YgJwzkPMvya3GAG.pVlzBXg81Oi..mHl3FHfWT1Ucac" + window._cf_chl_opt.cOgUHash);cpo.onload = function() {history.replaceState(null, null, ogU);}}document.getElementsByTagName('head')[0].appendChild(cpo);}());</script></body></html>