{"id":9239,"date":"2013-03-12T17:18:42","date_gmt":"2013-03-12T17:18:42","guid":{"rendered":"http:\/\/xmau.com\/wp\/notiziole\/2013\/03\/12\/psi_day\/"},"modified":"2013-03-12T17:18:42","modified_gmt":"2013-03-12T17:18:42","slug":"psi_day","status":"publish","type":"post","link":"https:\/\/xmau.com\/notiziole\/2013\/03\/12\/psi_day\/","title":{"rendered":"&psi; day"},"content":{"rendered":"<p>Ho appena scoperto da <a href=\"https:\/\/mathmunch.wordpress.com\/2013\/03\/12\/dots-and-boxes-choppy-waves-and-psi-day\/\">Math Munch<\/a>  che oggi \u00e8 lo &psi; Day! E che numero \u00e8 &psi;, vi chiederete voi? Semplice: \u00e8 la <a href=\"http:\/\/en.wikipedia.org\/wiki\/Reciprocal_Fibonacci_constant\">costante di Fibonacci reciproca<\/a>, data dalla somma degli inversi dei numeri di Fibonacci:<\/p>\n<blockquote><p>&psi; = 1\/1 + 1\/1 + 1\/2 + 1\/3 + 1\/5 + 1\/8 + &#8230;<\/p><\/blockquote>\n<p>Il numero \u00e8 circa uguale a 3,35988&#8230;; visto che questo \u00e8 il terzo mese e nella giornata odierna abbiamo toccato il 35,988% del mese (un po&#8217; prima delle 4 del mattino: ecco perch\u00e9 Jacopo stanotte si era svegliato a quell&#8217;ora reclamando ad alta voce dell&#8217;acqua!) il giorno \u00e8 stato dedicato a questo numero elusivo. Pensate che solo nel 1989 \u00e8 stato dimostrato che \u00e8 irrazionale.<br \/>\nPrima o poi mi decider\u00f2 a inventare un calendario di giorni matematici, mi sa :-)<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Me lo stavo perdendo!<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center 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