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: "mathematica.stackexchange.com",cType: 'managed',cRay: '91d8f500eb20fcde',cH: 'kcBkBWxhwFuWxK2jJRAZnhUEtly9lQv5c1_YkxugjZ4-1741506370-1.2.1.1-E_YTPV95D70IREB66rdnYiE_5YsjkjHjp8Ac13Mfyo3Xi_AtqYrsXmF1_7a8IffJ',cUPMDTk: "\/questions\/tagged\/operators?__cf_chl_tk=5tN06FrFEXEtfBp1_zKvgz7mWNm9U9hBH7qM1fQA6m8-1741506370-1.0.1.1-4oxpmJO1DBhr.vckBWMr_iBYtvmtRVn8GjgGY5g4LUk",cFPWv: 'g',cITimeS: '1741506370',cTTimeMs: '1000',cMTimeMs: '390000',cTplC: 0,cTplV: 5,cTplB: 'cf',cK: "",fa: "\/questions\/tagged\/operators?__cf_chl_f_tk=5tN06FrFEXEtfBp1_zKvgz7mWNm9U9hBH7qM1fQA6m8-1741506370-1.0.1.1-4oxpmJO1DBhr.vckBWMr_iBYtvmtRVn8GjgGY5g4LUk",md: "fCkDsMzxL3yuX9sU.0Sn8jZA8tFMuLCqNn0AZK9MXLY-1741506370-1.2.1.1-Nvwh8W0ldfOsFjJjSUB9zuMkyA5ZuaO2UoC.skmstX_d7i4dGzaJZx_.XS5NrEoZ86678eTDjDYgzn32vEbZ1NmGE6O0eJg.uOIEhbTl4GME2NpaVssslithsuU9qAchx5ErTZslqbEm4Plk8l_iX.dTY8LsIHJ.HKJYM07L7n.665wMAk0nQdP.oj5c8yiTWVXpoXeB6QH9yloKhyMd03Czgrvr.wHtZJ6VS43hPBrMKNaWuIYGchL1Ct9gQYFKXTDM3WET_miGQVk00tpBNE7EoDF5l40yrkUHfx47oThzcNSDDAE079Dfinra2aYySdN8DQQrcaa8_lZlfXdCyepwZ_0JDTmIKHO_1TV6Gl7_VxOEyVcORqA9GpzqqQ0FJ8gu8Wahi4CFYMAEbb.Nw6X_gq1hk7v9IrZSr0E.DRQMy6MUiFEJ7ba3ng2hOcXm74XMLc.yL.Q4Y5TA9RlvGlIProMCElT3OM5srRyPhX6uXXyIrA0ONsP.uO46R9VM2srST7DZpefuR0XqTLyRuDQqBX6fxxbBxWFHO6KaQZZT1X17yvC3UShelhMV7RstofcmKHSCGjoBhdkfY.2BrmCcuGsRUOGcyhdc8JhYtqm5mdsT2N4G2UPH3WVxJtBX.KzNVwRCwiFyDIkuLMt0Au90XHibVfC0DplXtvnMd4BF62r_yZS3K1LI2hAnj4FVZ.HndwQq7Xxe4emfACZM..6vMj7NomKhuAxfxFB6KVth_klcUgonbeyjZLBPakjkbruEORclra4Zg01yPizK87JfpZMm62ReF5mswlOc8.YHgG8592r8hYIceKByP5PIdwiv1qlPkKfJVZsh8wmbRPxtoHBJ78nTZ4ogbdCbvtCPGo3xKje4EWmE7kv0ihM8gHAzrYVaKt.9NScoEXjo8SlxW5KcujnrRN28g5_PXmLYhV357isDe0TtgvB_HpASmKkz1hkjWE0R2FH59upPxkYd7fxbg6U8Z5pSjpPIxoJzVJUKnp4wjU1_DNdWexr9dvb5d3HjErPerfYvX5tSTvly..Oc192wTfQBfFqK9TLxP.X4qPETyClradhU0GvOYb3zHi.IzwLVui0epcbArNrCDlSw9TVO2FBVbyzVLpl1XuNUgdKGw0Ec5MAxrUPns.HvoeLVfiEWnmRgKhhl059F7fPWdGPOKS6aooNlvH45iDfyrzXvweV6OlD_33brcdWwU2tzji_4qnVM4UoIelwRKPEqZShQNlBK4aiUJOeCREojny84q9Q.eQI8b_1TJV2Yj8ULsKZnK6JfWgsyQA",mdrd: "hmweHN6T5jg7JxMije3akeOmu1maXETlkXdQqVaD6BA-1741506370-1.2.1.1-W2Vmvs0tc8Ka4Dr1PqX1Kam0jWp0dh3tRpU6dw53ygqP7cl9po_qLtDe_SOnA.f1usCVwlkUI_e3ELPZJgIwpCzqcJqwLWnHwJwlEjH8QsmOwDQkx3H0RCoa8i5h9fCRh3LSCX8FhyA_naKsv2aY6LIi.yVI16SVXyz8ONj_lmr6rcFRyqnpWcMo9cVx50m58RV5Op9bdsEdBlTELJnPSmIlPCR7tQMSHTHaBt3nWfc8MvU9SLq1VB707EBKz2bkdVEWnwbFW9cDkbJNclAup.PGqXrIvShqNvfOVqWa_fX0hoCiG1CBK8EAiAHajGO0ivPFfXdw2Fuwkp6f2eejWyZSV_RLwwglt5LbSbku0NIh0qMDTRYZgXmdBqM3x_.ypLklXdPiGxINkbLUXn8OsBbc9SP1bRneiCAuu1iNJ5rLE3jZIbgBQxpsxcA9hvMvzowmOnlMnyBG6xUvfhEnNettWUcjwElM1gvv2H.n9LJT_leRPbk350Fg20oCpCuOJhlcd_g_Eg6TStHPgrmRJ1mlhh0AcknHZy06bchpV3Z78nrJ5Z96aNGe1dvAf6d3aIcbh6AaMIAhGNTjsJQC9AykGu7l3csUacf7YeawOROblPWUH78HgjHruBKcmhBlmwCyzG2E7YsSdtF1mws2SkhYgUvimwm2DoucmTTL7ze3L1qYatZziegWwolYD3LPgi7n39TdYz7plne8212c2voXIqRUAouzSAD9Xk3OrbPPI9EnI.FM1pJV5YVbogmNnj68_hrXhguFAck6P73_2iwP5gtMrB375ibeI3zy4KrOMiLRKUK0NAoRaKuFnjl2AsC5muL8oDPSLdVzda8XZnJunqoPWxkw.s6KeJ8qPle9G6hFIhoHZkVC_CTwLGSXyXJvGGOstcWGtMSpuiuNEWCJd82v7M9rHEuIY5jYHM6b_6LeUwsrAMfN.Oa7aGsgWhyl_EiY00Lmk278hTMxlD2GgY41cJWRHV1aoz83wxPtwbs1AnzYaT7mzeXfvHhIs88VTL3QN6t2dtNPosx30E7wky3s4nK9a26r2Nl1oJXWHA4Eq9J6tfSxa1N7EVR17fY4p1ur3dmRYvt7POWgpqtFtJWX3AN13svb5zOOPse41DtAE9VB8PiYHGlSKcJJ6wxKM8rifR5dvSNqrdNaUGr8fwqjIrrrrTN_4o_4jb0WJiKtUrdkC3QsIyrRGP4jlHHaj_84Nqv2t4SWeuabcPDvBt2ujROggkpHIENABTv.PFD9QX.qCVq6Z2LtJ4x7.p3ej5H2YDx9XcqkEyF6TUAgMKj96EQsl4c6OeVjUsOhd35K1.HrKoQje9nuC_JkN0XxaQMdseHy19oK3M06UgpltdnbAQ4Nhlq8Z0VwojeHW2XN4LCW.X_22FBlWUek631.n6fEDdPj6e6BhwT3NupLREyXDtbfpqvk_kwLJB_eOJ9TtyYtMyUksyIhfOWiFWVTwlM.7oXmaZ5DoT_5oRcQJ6b60ongm_Lz0L.Arkisg5_bSgfHro3q.mLaIJYraDkom5nyq5XIDMT3oP65EVUWWFJcZvlWrjNlDYuahXE28f5S1UCmhNcxJnKv.4hqyT3Xw5ehdcddqwa.Mfs_yK0a5F5nLfdnIHIrZa_tp1TNwOeFbwNx8KHSj4xrXlfEtEHBiDKKab5qmoy75D2qbAV_.apY1KcK0hAQ3oyATEknJXv1kIKrTIYcpv_CosisbsuDVE.382ngduV8m2x42zf0JkY9mngW.DUsAm2c8iwEqmvEpA1_XbGkuuzVPrW5rfypySn77tDZ1HXy8cB0HBCKPtWW3tr0X85t8j2_j.rpBMUxKt7ny0ZFsmNZ4blwvbRMrLRgTdluDwOdkZl3tqb0N3B7IQ6l5vM.o1dxC3F0iU7QBnljh8NomLeLbLWeF3KliwlJdPle5zCC.1bYR.0frkyqLx15EYrTGi5FyiE.7cuy3tcvBwOsXnwabsQxlLdkSxoP0dzp1TTt.fdVMw"};var cpo = document.createElement('script');cpo.src = '/cdn-cgi/challenge-platform/h/g/orchestrate/chl_page/v1?ray=91d8f500eb20fcde';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, "\/questions\/tagged\/operators?__cf_chl_rt_tk=5tN06FrFEXEtfBp1_zKvgz7mWNm9U9hBH7qM1fQA6m8-1741506370-1.0.1.1-4oxpmJO1DBhr.vckBWMr_iBYtvmtRVn8GjgGY5g4LUk" + window._cf_chl_opt.cOgUHash);cpo.onload = function() {history.replaceState(null, null, ogU);}}document.getElementsByTagName('head')[0].appendChild(cpo);}());</script></body></html>